View Full Version : FINALLY started BIG_CNC_LATHE conversion


FPV_GTp
07-22-2006, 10:40 PM
hi guys

OK , i see one familiar name in this forum and some Aussie like me.

but the true run down is im a motor mechanic and have some free time on my hands

I love drag racing and have a few fast cars and i want to go faster , presently building a 1200Bhp plus turbo 6 cylinder 4 litre falcon E series motor. will find out if i make the horse power once i get it on the heenan and froude engine dyno i run at work.

I'm in the process of contemplating ( have started converting , stripped the old lathe and just fixing her now so it looks good at least ) this old copy lathe to a CNC_lathe . I know it will not be good and fast as some of the CNC_machines out there in the market place like the Okuna's , Mazak' , Puma's , Hitachi Seiki's , Mori Seiki's and Pinnacle's and the list is endless.

But if i had the cash i wouldn't hesitate to buy a MIlling center and a lathe in cnc setup. Maybe in a few years time

It's more a hobby at this stage for me , i want to be able to make my own parts at a slow pace .

i see a great deal of knowledgeable people in here and cnczone.com and many other good websites.

so here it goes i have this lathe and have attached several pictures of it , it is a very robust unit so rigidity is not a issue.

Will have to make all the brackets and adapter to couple the stepper motors to the lathe. This is not a issue as i have other lathes and mills at work. But the problem is im new to electronics and CNC is not my strong point. Some sort of guidance would be appreciated as to the approach i take on doing this conversion .

Yes some may say its a big machine but i thought why do a bench top lathe when i can start on the big lathe and be done with it .

Its just a larger version of the small bench top unit and i want to be able to turn some bigger parts than what the limits of the bench top lathe will permit.

I plan to convert a pacific U2 universal milling machine also to a 4-axis cnc setup also which is sitting in a section of my workshop probably tackle them both at the same time

I'm one that does things BIG , now the stepper motors i had planned to use are http://www.kelinginc.net/SMotorstock.html ( NEMA 34 HIGH TORQUE STEPPER MOTOR 1812 oz-in, ½” Single shaft with flat, 180
KL34H160-62-8B ½” Dual shaft with flat: Price: $189 ( in stock)

this crowd has drivers and power supply also am waiting on a email back from them as we speak.

these stepper motors are probably over kill for the lathe and mill setup but for the price there selling them i figure just spend a little more and get some decent horse power steppers.

again im open to criticism and suggestions here guys , what are your thoughts i need all the help i can get am a fast learner , did bachelor of applied science , all math, science and computer studies at university back 20 years ago and kick my self in the head i didn't finish schooling . Did FORTRAN77 , basic , Pascal program writing back in 1984 now i am showing my age


1. stepper motors or servos ? size ? brands ?
2. stepper motor controllers ? servo controllers ?
3. power supply ?
4. spindle speed controller ?
5. Ball screws and nuts/flanges ? size and specifications ? what brands ?
6. what software ? sorry im not being biased here , i am looking into " Mach " ?

any help will be great here guys

and i'm extremely sorry if some of you think i shouldn't have posted this thread in this section , looked all over and thought this would be the best section for this post

there is no chronological order that i have written this post so correct me

cheers

HuFlungDung
07-22-2006, 11:01 PM
Off the cuff, I would say to avoid using stepper motors on large machinery, unless you can find a closed loop controller system that will detect and correct for lost steps. I do not think Mach will do this yet.

Ajax cnc or Camsoft cnc, that is a couple of the more often mentioned names around here.

The level of precision required for a useful lathe X axis is very high. This requires lots of steps, and to obtain decent rapid rates, you need a controller that can crunch lots of numbers, fast. Camsoft, and the Galil card that it often uses, can count as many as 12 million encoder counts per second.

Ajax can likely give you some advice over the phone about what you've got already that may work, or a complete system.

Camsoft, well there you'd be able to use a bit more of your programming smarts to write some logic. It takes lots of time, but, it is a versatile system. If you are going to do a mill and a lathe, you might get double use out of a Camsoft system and the time required to get it running. As a bit of a tinkerer hobbyist, you might enjoy the battles to make the system work as you envision.

Sorry, but I know of no really cheap way to do a professional quality retro, and on a larger lathe, you don't want any whoopsies coming out of the woodwork that did not originate in your g code. :)

FPV_GTp
07-22-2006, 11:06 PM
hi

We in Melbourne Australia have a newspaper called the " Melbourne trading post " , this newspaper has categories of different things for sale from cars to house hold goods to tools and machinery. Yes they are listed on the net and i was reading it and come across some guy selling ball screws.

I telephone him and with a few minutes i was on the road to his place.

He lives about a 1 hour drive from me on the freeway so i zoooooooooooooooommmm down to Geelong, to my surprises 3 of the 4 ball screws were NEW never been used or taken out of there wrappers.

The ball screws are German made by Steinmeyer and the purchase order papers come with the ball screws .

The ball screws are 40mm units , this one i have taken pictures of is 600mm long. the others are roughly 2000mm long . Does anyone read German all the documentation is in German ?

One of the longer ball screws and nut/flange was seized due to the fact there was a lot of grit on the shaft and i imagine inside the nut also.
again this size ball screw and nut is over kill for my lathe but they cost me for all four $150 so i couldn't not complain nor resist buying them.
Now that i'm on this forum , not be harsh on me when i ask this question , i'm new to CNC machinery and computer drawing software and software that controls the CNC machinery .

are there any threads a guy designed a tool change for a lathe has anyone got any other ideas of there own , would love to hear if you do and any pictures or information on a CNC_tool changer for a Center lathe.

what is the best softawre to run a CNC_lathe in 2 axis ? and why ?

Is there a demo version of the software on here that i can have a play with ?

cheers

FPV_GTp
07-22-2006, 11:48 PM
hi HuFlungDung

I/m confused now mmmmmmmmmmm

why is there any difference between a small ( desk top lathe) to a 2 tonne monster and bigger ?

other than driving 100 ozin to 2000 ozin stepper or srevo motors

i had a look at theses two websites Ajax cnc or Camsoft cnc thanks for that HuFlungDung , i will weigh the pro's and con's of all the systems out there

cheers

FPV_GTp
07-22-2006, 11:58 PM
hi

anyone used this card

http://cnc4pc.com/Multifunction_CNC_Board.htm

what other cnc drivers are there , guys any help would be fine


cheers

balsaman
07-27-2006, 12:21 PM
I would go gecko's and Servos. Forget the steppers.

Eric

arturod
07-27-2006, 01:15 PM
FPT,

Hi, I make the multifunction board that you posted earlier. That board comes with many bundled features that will make your life easier when retrofitting a lathe. I have other goodies like relays and index pulse index that you will find very useful.

There are a large number of options depending on what you need and want. If you are going to need high speed, and budget is not a problem, you should go to centroid, camsoft, galil, or others.

When doing lathe work, you might need speed on your axis is you run a fully automatic machine that needs to travel to each tool position. Geckos and servos should work ok, if you are not very high speeds. Consider steppers only if you are not going to do lots of traveling.

Arturo Duncan
http://cnc4pc.com

keithorr
07-27-2006, 02:08 PM
The bit about closed loop back to the software as opposed to just closed loop to the card or driver doesn't fly for me. If the machine delivers the product, and an error signal shuts things down when the servos can't keep up, then all is good.

There are options to take a pulse signal to a servo. I have camsoft, but I could have achieved the same results for less money. One thing camsoft has going for it is I/O and logic, but if I was turning bar stock and just needed to turn on a couple of devices, I wouldn't worry.

I think Mach with Gecko servo can keep up.

BobWarfield
07-27-2006, 05:45 PM
RE toolchanger, that's getting to be out there in the realm of lots of extra credit. Consider gang tooling first. You can mount a rear tool and get to 2 tools easily. After that you could envision 4 tools. After you've gotten proficient with that, you will have figured out how to do the toolchanger or more likely bought a lathe with one.

I will say that I have heard it is very hard to retrofit a new control to an old CNC lathe. Your project is not that, and I have never heard the details of why it is challenging, but I have heard it more than once.

The last thing I will mention is that lathes are a bit of a stepchild for Mach. I wish it wasn't so, because I am also working on a CNC conversion, but the lathe functionality always significantly lags the mill functionality, and I mean by a lot. I am hopeful that Art will find more time to work on the lathe piece if more people get interested.

Best,

BW

balsaman
07-27-2006, 09:54 PM
Get the tool changer right outta your head. No need to concern yourself with changing tools automatically until you got the lathe working under cnc control. One challenge at a time man.

E

FPV_GTp
07-27-2006, 11:24 PM
hi

need some form of a tool change to drill , bore and internal threads and tapers

I saw on a small bench top lathe that i nearly purchased but realized i was going to pay way to much for what i was getting after i did my homework

The bench top lathe is a training lathe a company in Adelaide Australia makes them for tech schools , way over priced i could purchase a second CNC old mazak or okuma for the price they wanted for theres.

But of the topic now the little lathe had arranged on the X- axis cross slide 4 tools in there holders , the way they where orientated mad it possible to machine large objects in the 3 jaw chuck

will try and find there website and upload a picture so you people can see what im am talking about. nifty little setup

At this stage i do have a budget to meet on this project and it seems everyone has divide differences on what software to use and hardware ?

Seems everyone is saying stay away from stepper motors and use servo motors ??

What is a servo motor like on the insides and one have a picture of one pulled apart ?

I have pulled apart small stepper motors so know what there construction is like but can not find anything on the web to see inside a servo motor cause everyone is raving on about servo motors , there the best thing introduced to cnc machinery since the invention of sliced bread


cheers

FPV_GTp
07-28-2006, 08:15 AM
FPT,

Hi, I make the multifunction board that you posted earlier. That board comes with many bundled features that will make your life easier when retrofitting a lathe. I have other goodies like relays and index pulse index that you will find very useful.

There are a large number of options depending on what you need and want. If you are going to need high speed, and budget is not a problem, you should go to centroid, camsoft, galil, or others.

When doing lathe work, you might need speed on your axis is you run a fully automatic machine that needs to travel to each tool position. Geckos and servos should work ok, if you are not very high speeds. Consider steppers only if you are not going to do lots of traveling.

Arturo Duncan
http://cnc4pc.com

"I retrofitted a Hardinge HC CNC lathe that had an old bandit control. The machine was working OK with the bandit control, but I had the same problem as you have. Dealing with old electronics and an awkward control (compared with what Mach3 can do.) This lathe runs fully automatic with 10 feet power bar feed and an 8 post tool turret.

Here is a brief description of what I did and how much it coasted:

I used a PC with two parallel ports. I used two cnc4pc bidirectional boards (that I make and sell). The second one was set to use pins 2-9 for input, so I had a total of (5+13) 18 pins for input, and (12+4) 16 pins for output. The cost of these cards is $26 each. I also used an A4 Power supply (that I also sell) for providing 5 and 12vdc that is used to power all the circuits. These power supply costs around $29.

I used the original power supply and motors, but, replaced the tach and resolves with E2 2000CPR encoders for x axis and 1000 CPR for y axis. These encoders are about $32 each. I also replaced the old drivers with G302 from Geckodrive, this cost $114 each. I also replaced the stepper driver that runs the motor for the tool turret with a G201, also costs $114.

I replaced the nice 500CPR encoder that was mounted on the spindle with a C3 - Index pulse card (that I also sell). This card costs $16. With this index pulse I am able to thread and run a closed loop cycle on my spindle. I replaced the awkward speed control with a Hitachi VFD that costs $330, and also used the C6 – Variable Speed control board (that I sell). This board costs $27. With this board you configure your spindle just as you would a step and direction driver, and with the index pulse feedback you have 100% control of your spindle’s speed.

I also replaced the mechanical home switches with the same Index pulse card that I used on the spindle. That way I get a very accurate homing. For the turret home I still used the original mechanical relay that came with the machine. There is no need for precision here, since the turret has a turret lock that holds the turret in place.

I also used the C5 – Solid State Relay Board (that I sell for about $46) to control; turret lock, coolant pump, collect closer and power bar feed, and the cut-off tool.

I also use a C4 – Safety Charge Pump (that I sell for $17) to control the system along with the e-stop switch.

I also installed a 150CPR encoder from us digital (about $32) that acts as a manual pulse generator.

The only thing that I miss from the old control was the speed of the servos. In terms of control I lost nothing and gained lots of features. I currently plan on installing proximity switches to program tool checks o other things. The total investment was extremely low compared to the benefits that I achieved.

Arturo Duncan
http://cnc4pc.com "

Hi Arturo Duncan

now i read this quote you posted in this thread link http://www.cnczone.com/forums/showthread.php?t=20895&highlight=big+lathe page 2 of the thread u posted what i have highlighted in bold blue and visited your website and you have all the goods i need to convert this manual lathe to CNC_lathe , i want to use either a laptop or a PC which there are heaps around the place . I want to be able to basic turning , boring , taper_turning internal and external, thread cutting internal and external .

Arturo Duncan i'm new to all this and ask you would you be interested in giving me guidance in a complete conversion on my old_copy_lathe to a cnc_lathe , I will purchase what is need from you and assemble it at work my end.

I ask the same question like NC Cams
Master Machinist , it is just a lathe with a X and a Y axis a 2-axis , even on OLD CNC machines why cant you just bypass the old fanuc controller and just use the stepper motors/servos/ballscrews and yes some of the hydraulics to operate the chuck(s) , tailstock . coolant pump and any other things that need to be switched on or off , lights , door safety open etc ????

I have spoken to a few people my end of the world in Australia and some of the responses i get is how big is your bank balance , and i look at them and say none of ur F@#Ken business. Everyone wants to get rich quick.

And some of the sales pitchers i get when i tell them what i want to do with my manual lathe they all say its impossible to do ??? and when i say why can people convert small desktop lathes and mills with succes they just ramble on all this bulls@#t to me . I PMSFL

lets see what happens here

cheers

FPV_GTp
07-28-2006, 09:00 AM
hi

Bought another center lathe with gap bed and a 3 meter bed , come with some bits , a 3 jaw chuck , 4 jaw chuck , 3 jaw soft chuck , 5MT live center , a between center bung , 4 chuck keys , tool post spanner, travel steady and fix steady. Missing a face plate

i need to adapt the chucks to the head as it had some camlock chuck arrangement on it , will be easy job and just go over the machine and a coat of paint and she's is ready for work

I have some big rollers i need to machine up , i want to make a sheet metal roller and a few other machines that i need.

and no i don't want to convert her to CNC LOL

I saved her from the metal scrap heap and i have a few jobs i need to do on her , she looks good and I will get her running right

cheers

FPV_GTp
07-28-2006, 09:20 AM
woooooooooo

had a look a MAZAK, MULTIPLEX 6200, LATHE, MULTIPLEX, OPPOSING SPINDLE beautiful piece of machinery

if ii had the money would not wait one minute more would buy one straight away

tomorrow is saturday here in Australia and the big tattslotto draw is on first prize is $20,000,000 ;) will buy one ticket for that draw

just in case i win ;) and forget about the red ferrari

cheers

FPV_GTp
07-28-2006, 09:35 AM
hi

has anyone had a look at doing something like what this guy did ??? Converting an Ordinary DC Motor to a Servomotor ??? have a look at his website http://truetex.com/servomod.htm

cheers

balsaman
07-28-2006, 10:02 AM
When I say use gecko's and servos, that is what I mean. Gecko 320 drives www.geckodrive.com and ordinary DC motors with encoders attached.

BTW I am not blowing wind. I have converted a milling machine using Geckos and servos (DC motors with encoders attached) and Mach 3 for software. Here are just a few parts the mill has made. I don't sell any of these products.

Beware of taking advice from those who are trying to sell you something....

E

FPV_GTp
07-28-2006, 10:37 AM
When I say use gecko's and servos, that is what I mean. Gecko 320 drives www.geckodrive.com and ordinary DC motors with encoders attached.

BTW I am not blowing wind. I have converted a milling machine using Geckos and servos (DC motors with encoders attached) and Mach 3 for software. Here are just a few parts the mill has made. I don't sell any of these products.

Beware of taking advice from those who are trying to sell you something....

E

Hi balsaman

had a look at the gecko drivers and many other drivers and stepper and servo motors. Seems the way to go but there are many other options out there.

Balsaman what software are you using ?

what are the advantages of servo motors as opposed to stepper motors ?

I want to make fuel injected parts , trumpets , fuel rails , fuel bungs , fuel injected manifolds , throttle bodies , webber style throttle bodies , holley carburetor style throttle bodies with a square bore base 4 venture in different sizes .

Also for a particular vehicle want to make and modify front stub axles for larger brake conversions.

finally found the link to the australian guys in Adelaide that make small cnc lathes and mills for training tech schools , not cheap link is http://www.axmell.com.au/Hercus/CNC%20PAGE/CNC_Index_Page.htm

they make some sort of four position TOOLPOST changer "A choice of Tool post and holders are available. The NOVIM is fitted with a four position manually operated toolpost. An eight position Automatic turret is an option. The turret is activated by a PC command and is bi-directional. A quick change style toolpost is also an option. "

i spotted a different setup on a lathe some guy was selling out my way where on the X cross slide there was 4 different tools holders positioned on the table where the software of the lathe selected which tool to use

The lathe that i want to convert to CNC-Lathe i will be mainly doing turning around the chuck area but at times will be turning ford 9 inch axles to the specs that i need as i do a lot of 9 inch differential modifications for different Australian cars have even done one for a 240 Volvo and some other weird cars.

So i have to machine the back of the flange and flange diameter bearing and seal diameter and the axle shaft length where i cut the spline , so also machine the spline diameter.

Had 5 differentials to do in the last week , manually machining theses axles is very boring work , this way if i had a cnc_lathe i could program the different axle lengths for all the different cars

cheers

HuFlungDung
07-28-2006, 10:51 AM
Servo motors don't have resonance issues like steppers might/can/do.

Closed loop feedback to the control helps assure that your machine is in correct position, and is not slowly getting closer and closer to the chuck with each part, until you start to wonder "what is that ticking sound?" :D

Steppers are good to run stuff that doesn't have highly variable loads, or are non-critical in nature. A cnc lathe under control is still a dangerous piece of machinery, and the bigger they get, the more damage can be done. You want the most reliable control you can get, not something that may or may not move exactly where you told it.

arturod
07-28-2006, 12:20 PM
FPV,

What I did was a bit simpler because I started with a lathe that had all the mechanical stuff for cnc already in. What I did was to replace the old control with a PC and a box with all the electronics that I make. This lathe is where I test all my stuff. I know I should post some pics of it. It is 100% functional. The only thing I miss is the very fast servos it had (the servos it currently has are the same, but I changed the drivers to G320s). The high speed was nice, but I really do not need it. You explain it very good with the Ferrari example. In my opinion the axes speed really hurts while tool changes. These are my opinions on the most relevant aspects of the lathe conversion:

1. Axes motion control. You want to use steppers. Check out some of the videos for CNC machines using stepper, if you can live with that, go ahead. For a couple of bucks more you could probably go with servos and probably do 50% faster. Geckos are great, but if you’re in Australia, you might consider rutex. I have no experience with them.

2. Tool Turret. Some people just gang up the tools on the table. The good thing is that it is simple, the bad thing is that you need a long x axis to be able to fit all the tools, you are also limited in space; you probably always take the risk of crashing a tool. It probably also has to do with how you do your programming. Another option is to use a 4th axes cnc indexer, John Stevenson did http://machsupport.com/forum/index.php?topic=970.0 . Keep in mind you MUST lock the turret while cutting. You MUST use some kind of index sensor to make sure the control does not loose control of the turret. My machine has a pneumatic lock and I use the index pulse card for homing the tool turret. Works fine for me.

3. Power Bar Feeder, Pneumatic Chuck, Cut-Off Tool. I have no mechanical experience with this, they came with the machine I have. I have seen many plans on the internet that will help build your own. I just replaced the old relays with one of my 4 relay boards. I also control the coolant and turret tool lock with these relays. It is all very simple, you would connect the relay just as you would a regular switch.

4. Control Software. I use Mach3, so far it has everything I need; tool tables, etc. I have written simple visual basic macros to control the turret and tool changes automatically. I created M commands for controlling bar feed, cut-off tool, pneumatic chuck, etc... Most are pretty simple, just using activate and deactivate commands, and sensors (index pulse card, and switches that already built into the machine when I got it). For example, if I did a bar feed cycle, the machine would stop until the chuck was locked and the sensor activated.

5. Variable Speed Control. This is too easy; I just bought a $300 VFD and connected with one of my variable speed control boards. This comes built in the Multifunction board.

6. Safety Charge Pump. A lathe is an EXTREMLY DANGEROUS machine. I learned this when once my PC froze (you know, windows xp). The chuck opened automatically and the bar feed pushed the ½” x 3 feet rod at 2000 RPMs across the shop. I always tell this story to people that are attempting to retrofit a lathe so that they take appropriate persuasion. Now days all the relays, locking cylinders lock all the devices in case of a power or PC lose. A safety charge pump (this feature is also built in the multifunction board.)

7. Threading. I use one of my index pulse cards; Mach does the rest, too easy.

8. I/O Many people will tell you that you cannot get enough I/O from the parallel ports to convert one of these machines. Keep in mind that you can always use a modbus device for additional I/O. I have a modbus device, but it is just for testing purposes. The machine runs with it. I have a two parallel ports, the second port has pins 2- 9 for use for input. This is how my I/O looks like.
OUTPUT INPUT TOTAL
LPT1 12 5 17
LPT2 4 13 17
TOTAL 16 18 34

The features I have are:
a. I control 3 axes using G320 with US Digital encoders on the motors that came with the machine. I use a G210 to run the stepper motor that runs the tool turret.
b. The machine has homing switches for all axes, including the tool turret, so the machine homes all the axes automatically.
c. I have encoder feedback from the axes fed back into mach. I do nothing with this info at this time, but I write a simple program that could compare the axes position in the control software and compare it to the feedback position, and take some action. I am not sure if some people will call this true closed loop, but for all practical reasons I guess it could work as closed loop.
d. I have an MPG, which is a 250 cpr encoder that helps me position the axes. Works very nice.
e. I have an index pulse sensor for threading. It also reads the actual spindle position.
f. I have VFD with one of my Variable Speed Control Boards that control the spindle speed. I have it configured as a closed loop system with the index reading from the spindle, the spindle speed is very accurate.
g. I mentioned earlier, I control the bar feeder, pneumatic chuck, coolant pump, turret lock, and cut-off tool.
h. The E-Stop is just an NC switch connected to one of the input of the cards. My Cards have an external enable pin that gets disabled by the safety charge pump and lock everything in case of emergency.

I believe this covers most relevant aspects of my experience. Please do not hesitate to contact me if you need further advice.

Arturo Duncan
http://cnc4pc.com

NC Cams
07-28-2006, 03:31 PM
Paragraph #6 in post 19 is EXACTLY why I will NOT use any form of Windoze to control a CNC. Any O/S that lets the processor take control of what's going on so it can do what it wants/needs to do is a dangerous entity.

I can not be convinced that you need a multitasking machine for a lathe or mill controller. If Bridgeport could get a 386, 486 or Pentium 133 to run a mill, lathe, VMC (4 axis plus spindle speed) and surface grinder with the same interface card and DOS software in 1996 or thereabouts, why do you need Redmond's latest experiment in incopletely developed O/S to try to reinvent the wheel today???

PC104 back planes abound out there - can't say there is no more support for ISA. Pricey, yes. Not available/supported??? Hardly.

The way I see it, steppers are low cost and efficient controllers. However, they're trying to use fancy digital electronics to simulate truly analog motion. Adding encoders to warn of errors is too much too little too late. Take the encoder and use it up front, not after the fact.

Besides, sooner or later, the speed factor you're trying to achieve will result in resonance with a stepper - resonance that can't necessarily be tuned out. See the circle cutting problem thread elsewheres on the site.

Servo's on the other hand are essentially analog devices. If you've ever "driven" an RC car with digital servos versus analog ones, you can literally "FEEL" the difference. The digital servo moves in steps and shudders, the analog one moves in linear proportion and smooth fashion.

Need instant proof??? Take your mouse and make a perfectly diagonal line across the screen - it can't be done because it is a step fuction device. You get closer to perfect as you add steps to make smaller and smaller errors occur but you're still dealing with a step function device.

Servos have their own problems but torque and speed are not usually part of those problems. For a hobby type lathe, you could deal with sterpper issues. For industrial iron like you're working with, you're going to need a BIG stepper. At what point will you be approaching the cost of a servo and will it perform when it has to MOVE the iron???

My Fanuc powered lathes have 90vdc motors, 12 amp continuous. Rated speed is around 3000rpm. Torque output is huge due to the pulsed DC drives they use. If you plan on moving the carriage quickly, you need OOMPH. An equivalent DC drive today would need comparable voltage but probably 20 amp continuous/50amp surge rating due to the current surge. At that point, the only stuff close to being able to drive it would be one of Advance Motion Control's DC servo gems. Don't think Gecko or Rutex make anything that robust

DON'T buy anything until you decide/figure out what you need to have to move what you're trying to move. Look at similar commercially made CNC lathes and see what they used for power/drives/etc. Perhaps it might be expensive but, in an industrial setting, properly engineered stuff simply runs.

As simple as you'd think a lathe would be to CNC retrofit, the separate lathe retrofit thread shows that the task is frought with peril and unfulfilled promises. The reason lathes don't get the attention is simple economics - far fewer lathe retros so why bother???.

Too bad Bridgeport never did a Ezpath lathe retrofit kit. At least it worked and was well devloped. More than what can be said for some of the other lathe retrofit systems out there.

balsaman
07-28-2006, 04:18 PM
What is your budget for the conversion?


hi guys

OK , i see one familiar name in this forum and some Aussie like me.

but the true run down is im a motor mechanic and have some free time on my hands

I love drag racing and have a few fast cars and i want to go faster , presently building a 1200Bhp plus turbo 6 cylinder 4 litre falcon E series motor. will find out if i make the horse power once i get it on the heenan and froude engine dyno i run at work.

I'm in the process of contemplating ( have started converting , stripped the old lathe and just fixing her now so it looks good at least ) this old copy lathe to a CNC_lathe . I know it will not be good and fast as some of the CNC_machines out there in the market place like the Okuna's , Mazak' , Puma's , Hitachi Seiki's , Mori Seiki's and Pinnacle's and the list is endless.

But if i had the cash i wouldn't hesitate to buy a MIlling center and a lathe in cnc setup. Maybe in a few years time

It's more a hobby at this stage for me , i want to be able to make my own parts at a slow pace .

i see a great deal of knowledgeable people in here and cnczone.com and many other good websites.

so here it goes i have this lathe and have attached several pictures of it , it is a very robust unit so rigidity is not a issue.

Will have to make all the brackets and adapter to couple the stepper motors to the lathe. This is not a issue as i have other lathes and mills at work. But the problem is im new to electronics and CNC is not my strong point. Some sort of guidance would be appreciated as to the approach i take on doing this conversion .

Yes some may say its a big machine but i thought why do a bench top lathe when i can start on the big lathe and be done with it .

Its just a larger version of the small bench top unit and i want to be able to turn some bigger parts than what the limits of the bench top lathe will permit.

I plan to convert a pacific U2 universal milling machine also to a 4-axis cnc setup also which is sitting in a section of my workshop probably tackle them both at the same time

I'm one that does things BIG , now the stepper motors i had planned to use are http://www.kelinginc.net/SMotorstock.html ( NEMA 34 HIGH TORQUE STEPPER MOTOR 1812 oz-in, ½” Single shaft with flat, 180
KL34H160-62-8B ½” Dual shaft with flat: Price: $189 ( in stock)

this crowd has drivers and power supply also am waiting on a email back from them as we speak.

these stepper motors are probably over kill for the lathe and mill setup but for the price there selling them i figure just spend a little more and get some decent horse power steppers.

again im open to criticism and suggestions here guys , what are your thoughts i need all the help i can get am a fast learner , did bachelor of applied science , all math, science and computer studies at university back 20 years ago and kick my self in the head i didn't finish schooling . Did FORTRAN77 , basic , Pascal program writing back in 1984 now i am showing my age


1. stepper motors or servos ? size ? brands ?
2. stepper motor controllers ? servo controllers ?
3. power supply ?
4. spindle speed controller ?
5. Ball screws and nuts/flanges ? size and specifications ? what brands ?
6. what software ? sorry im not being biased here , i am looking into " Mach " ?

any help will be great here guys

and i'm extremely sorry if some of you think i shouldn't have posted this thread in this section , looked all over and thought this would be the best section for this post

there is no chronological order that i have written this post so correct me

cheers

NC Cams
07-28-2006, 04:44 PM
Don't even consider the info on Ajax's site as valid for a budgetary estimate. Yes, they'll offer a $2500 USD or so package, UNTIL they find out what you want to drive. It will easily balloon to over $4k USD

Then, none of your stuff will work, buy ours, Or, they'll contend it is outside the realm of DIY and send you to the Centroid site - that gets into the real high 4/low 5 figure range in USD.

Fadal and Fanuc are in the $8K to $10K range but their lathes work.

A lathe is NOT a mill and you can't use mill hardware as a budgetary estimate.

Caveat emptor...

FPV_GTp
07-28-2006, 07:57 PM
hi balsaman , between $4k and $5k hopefully ???

do not want to pay commercial prices , im looking at how these guys have converted little bench top cnc lathes

i know things will cost more for the bigger lathe , which is normal.

as far as software i have seen some cheap as $200 to $300 right up to $3000 to $4000 USD and i imagine there is even more expensive software around.
same applies to the hardware of the electronics.

ball screws and single and or double nut preload ball screws , i have seen a lot f variations again in prices

a PC or a laptop there are heaps of them around for next to nothing in price
old 486 will run most of the programs out there considering the old very early CNC lathes and mills had very old PC boards in there and functioned OK to a point until you overload the memory space on them LOL

machining and making brackets is not a issue for me i have lathes and mills at work and a friend has 2 cnc lathes and i cnc milling center at work so if i need some things machined it can be handled also.

lets see what happens , it is just good to see some of the peoples views and inputs thanks guys.

cheers

NC Cams
07-28-2006, 09:54 PM
The ONLY and I do mean ONLY system (believe me I looked!!!!) that will run a lathe on "free" 386, 486 or 586/Pentium boxes was sold by Bridgeport as their Ezpath lathe with DX32 system (sold in mid to late 90's). THe same system ran CNC mills, lathes, 4 xis VMC's and surface grinders.

The Ezpath 2 or 2SD lathes would do all the trick stuff you'd ever want to do with tool changing, bar feeding, etc. This would be a DIY'ers DREAM, if ONLY it were offered on the aftermarket. The system involved a plug in ISA PLC board plus some external break out boards. These PLC based boards interfaced to industry standard servos and/or spindle drives. With simple plug in harnesses that any decent DIY 'wirer' could duplicate from a simple kit, it was darn near a plug and play system and very well integrated system.

IF (big IF) you could still buy the proprietary pieces and software from Bridgeport (don't think you can), you probably could do a retrofit.

BUT you'd have to do a lot of parameter engineering on your own to somehow 'tell' the system that it had miraculously been transformed from what it was to what it now would be. The parameters are NOT intuitively obvious to start hacking.

You'd get NOT a single word of help from Hardinge - they are clueless about support. I got lucky and the guy or two who did know gave me the name of field guys who knew the system and these guys were very helpful. They'd hardly be able to help you, however due to your location with respect to the USA.

Any factory trained Bridgeport service guy could EASILY tune the Ezpath system but don't hold out lots of hope. Even my service guy who respects what I can do with a machine and humors me with special support if I prove to him that it's viable, winced when I asked if it were possible to do a retrofit with this system.

Trouble is, there is/was too much that went sour when Bridgeport folded and the folks who know the workings of the system moved on. Sadly, they put it all behind them and do other things now. Hardinge is not doing much if anything to make parts availble for anything outside of a Bridgeport mill. Heck, they even use someone elses controller for their current "eztrak".

Cost if you want to do it anyway???

Who knows. All the parts are HUGELY explensive as they're no longer made by Bridgeport/Hardinge. The service industry is controlling the availability of remaining good hardware.

How??? By selling the boards on on an exchange basis (to keep control of the cores). Only EMI can really be trusted as they are staffed by some of the guys who developed the system and they service it exclusively pursuant to an agreeement with Hardinge.

I thought EXACTLY the same as you re; using a PC to do a retrofit of an existing CNC lathe with an antiquated controller. The "lathe retrofit thread" clearly outlines the challenges you/we face in the attianment of our goals.

Sadly, I've come to the conclusion that asside from Mach (NOTE: some of the early versions (especially the DOS versions) still in use are NO LONGER supported by the developers. Thus, Mach or EMC is/are the only inexpensive system out there. And Mach needs XP which is something I refuse to trust to run a CNC anything.

In my estimation step/dirction controls don't do real time "driving". They're always and at best, steps behind the parallel port even with servo feedback. The limited bidirectional data stream offered by the parallep port (even 2) is ultimately a communication bottleneck.

The machine will stop IF things get too many steps behind but the PC is still only working in step/direction mode as opposed to true direct control of a servo via a PLC ala the direct control path used by the PLC in the defunct Bridgeport system.

Good luck in your endeavors. I know what you seek, been there done that and still looking......

balsaman
07-29-2006, 12:10 AM
Mach 3 on XP (recommend a minimum of 1 Ghz. comp) is your best bet running Gecko's (or rutex) and servos on ball screws with a gear reduction using timing belts. You should be able to do this for under $3,000 easily, prolly less.) This would get you the best setup FOR THE MONEY.

E

FPV_GTp
07-29-2006, 04:38 AM
Mach 3 on XP (recommend a minimum of 1 Ghz. comp) is your best bet running Gecko's (or rutex) and servos on ball screws with a gear reduction using timing belts. You should be able to do this for under $3,000 easily, prolly less.) This would get you the best setup FOR THE MONEY.

E

hi balsaman

there are still heaps of laptops with Xp very cheap and greater than 1 Ghz speeds

I plan to use large stepper motors or large servo motors havent yet decided

ball screws will be min 25mm shaft diameter and possible 30mm on the y axis

maybe.

Do you honestly think i will have to use some form of gearing ? using timing belts and toothed pullies and a reduction of 2:1 ratio gearing will required with such large torque stepper or servo motors ?

I just planned to direct couple the high torque stepper or servo motors to the ball screws.

But if i need the extra speed for finer cuts or speeding the cuts thats a different story.

Since this is my first CNC converions to a manual lathe , just a question

What ball screw pitch would be the best for the lathe X-axis and for the Y-axis ?? there are different pitchs in ball screws also coarse threads and fine threads so which is better for the lathe feeds.

I assume from my own experience that fine thread ball screws will give finer cutting per turn and the coarse thread ball screws will give more a cut per turn

All will depend on the speed the motors are turned and i don't know what adjustments or fine tuning features there are in the software , I plan to use mach3 for lathes.

What other lathe software is there avalaible at a reasonable prices for amateur cnc-apprentice-machinest ? ;)

cheers

arturod
07-29-2006, 08:12 AM
FPV,

One last advice; DO NOT USE A LAPTOP FOR RUNNING MACH. I know they look very sexy on the machine, but there are many issues about the hardware, and how battery saving issues messing around with the processor’s speed. Please watch NC CAM’s comments. I am a very happy user of mach and winxp, and I do recommend it, but please do not take it for granted. Follow Art's recommendations on how to set it up, and please, use a dedicated machine. If you find that machine is not reliable with winxp and mach, please do not try to fix it, change the PC. I understand you must balance your budget with the final product you need or want. I think none of us can tell you if you need to buy a compact or a pickup truck. The only thing that you can not play around is safety. Do not attempt to play around pneumatic chucks, tool turrets, and bar feeders unless you know what you are doing. I know the way I say it make it look like wiring all the gadgets is pretty simple, and it is, but if make an error estimating how a relay, solenoid, or valve will behave on a certain circumstance, then you run into safety issues.

Arturo Duncan
http://cnc4pc.com

NC Cams
07-29-2006, 09:14 AM
I dunno if the "Please watch NC CAM’s comments" in Arturo's prior post were accolades or criticism. At this point, a dose of reality wouldn't hurt to be considered.

Retrofitting a lathe is NOT easy. It becomes ESPECIALLY hard if you're trying to convert a manual one to CNC. I simply wouldn't even THINK of doing it an I've done some agressive machine conversions to my CNC lathes and mills.

I have existing CNC lathes. Simply replacing the controller with a PC based system has not been possible - what it would take to engineer and fit ball screws and drives to a manual lathe ain't easy even if one has an engineering background.

Integrating the new stuff with all the electronics is ANYTHING but plug and play. Finding and figuring out the encoders alone is a nightmare and I'm pretty good at finding PDF's for industrial equipment. WIthout a proven wiring and/or ladder diagram to go by??? Recipe for a disaster.

There are a plethora of PC's out there. Some run fine with XP and some don't. Some guys have trouble with parallel port driving and some don't. USB to parallel converters have had their share of problems. Like Arturo says, DON'T USE A LAPTOP!!!! I simply won't use XP. You make the choice.

In this case, the member expressed an interest in using legacy PC's. That pretty much precludes the use of XP based Mach or XP'd ANYTHING - PERIOD.

Moreover, the earlier versions of Mach' s that run on the type of DOS boxes he was planning got use are NOT SUPPORTED ANYMORE BY MACH or they DON'T RUN LATHES. Who do you call when an unsuported software pukes or won't run at all????

The last thing this guy needs, especially with the path he's expressed interest in traveling, is to get involved with legacy software that's NOT supported. We already know that the low dollar hardware he want's to use won't run XP.

I'm not trashing Mach. Many people use it and it satisfies their needs just beautifully.

However, I got the impression that some of the more crafty users of it know how to write code or are MUCH more computer savy than I with regard to integrating it with their particular machines.

When I contacted Mach about my intentions on a lathe retrofit, the system was ruled out as being viable when the words "you'll have to write some code to do that" were found in the reply. Sorry, I don't write code as my youth was apparenlty misspent in not learning to do so. Custom code writing is not something the Mach creator does and that's understandable.

I'd contend that my needs and those of the member from Australia coincide. We're techincal people who are not affraid of DIY projects. We probably can both load software and run it. We an also wire, rewire and troubleshoot wiring in machinery. Mechanical component development is something we can readily do/understand.

We want/need a CNC whatever to make stuff for us (in my case to support a business). Hence a hobby type system is not quite suited for my needs. I dunno if a hobby type system will fit our Australian friend's - he'll have to answer that.

Howver, my interest in and ability to write code to make a machine work is simply NOT going to happen. Where do guys like us to to get what is essentially a "component based" DIY system for CNC retrofitting???.

Mach, Ajax/Centroid, MDSI and/or Camsoft have already been investigaed and found to be incompatible with the equipment and or skill levels available to me. They are ouside the realm of affordability of my struggling little business or too much DIY which I simply can't do as a part of day to day business operation.

If "watch" my comments is meant to emphasize the insight I"m trying to provide. I've done what I chose to do - keep someone from making a horrible mistake.

If "watch" means to ignore what I say because I've misspoken, I'd contend I was misheard.

My particular needs are simply not met by what's offered by Mach or remain unsatisfied by the "write the code" issues with any number of softwares including MDSI and/or Camsoft.

The issues outlined by the respondants of the separate lathe retrofit thread with the other commercial packages mentioned speaks VOLUMES. The run around I personally got and others reportedly got from Ajax was beyond insulting.

At this point, it would seem that our friend from down under needs to revisit and/or rescale his priorities.

He's simply not going to get old DOS boxes to do what he's trying to do via a retrofit - the stuff to do it doesn't exist or isn't supported anymore.

Moreover, I'd contend that retrofitting an old manual lathe with CNC control, ball screws and all will cost MORE that what he could buy a fuctioning Expath lathe from here in the states.

BTW, the Expath WOULD run on the DOS boxes he's interested in using - that's what they used in them. Finding one of these gems is easy - the shipping to Australia would be a whole 'nother issue.

balsaman
07-29-2006, 09:29 AM
hi balsaman

there are still heaps of laptops with Xp very cheap and greater than 1 Ghz speeds

I plan to use large stepper motors or large servo motors havent yet decided

ball screws will be min 25mm shaft diameter and possible 30mm on the y axis

maybe.

Do you honestly think i will have to use some form of gearing ? using timing belts and toothed pullies and a reduction of 2:1 ratio gearing will required with such large torque stepper or servo motors ?

I just planned to direct couple the high torque stepper or servo motors to the ball screws.

But if i need the extra speed for finer cuts or speeding the cuts thats a different story.

Since this is my first CNC converions to a manual lathe , just a question

What ball screw pitch would be the best for the lathe X-axis and for the Y-axis ?? there are different pitchs in ball screws also coarse threads and fine threads so which is better for the lathe feeds.

I assume from my own experience that fine thread ball screws will give finer cutting per turn and the coarse thread ball screws will give more a cut per turn

All will depend on the speed the motors are turned and i don't know what adjustments or fine tuning features there are in the software , I plan to use mach3 for lathes.

What other lathe software is there avalaible at a reasonable prices for amateur cnc-apprentice-machinest ? ;)

cheers


About the only other software out there is Turbocnc www.dakeng.com, and I have tried (and bought) both. Mach is better but requires a faster PC. Tcnc runs in DOS. BTW I only have experience with mills.

Steppers are a low speed, high torque device, and can be connected direct to the ballscrew via coupling. Servos are lower torque, higher speed and almost always need to be geared down. Go with 2:1 or 3:1 for ball screws with a 5 TPI pitch. Higher ratios may be needed for lower pitch screws.

Do not go with steppers on this lathe. Servo's are way cheaper for this size a machine (ever priced the high torque stepper motors?), and more reliable because the drive can detect if there is a positioning problem and shut you down so you are not making bad parts and also possible prevent a catastophic crash.

If going Geckos search the online surplus places for DC permanent magnet motors in the 50-70 volt range that draw 7-10 amps and RPM in the 1000-2000 range (geckos are good for up to 80 volts). Modify these these for 250 CPR encoders from www.usdigital.com. Rutex makes higher voltage servo drives so the DC motor voltage can be higher if using theses drives.

E

NC Cams
07-29-2006, 12:03 PM
Balsaman: Lathes are a TOTALLY different animal than mills.

For a mill program to even come close to doing a lathe, it would have to be capable of doing SIMULTANEOUS motion in Z and X axes - such motion is needed for thread and/or taper turning.

Essentially, only program that would accept an encoded signal from the spindle (ala a VMC or sophisticated lathe control) would even have a hope of working for our Australian friend.

In the "lathe retrofit" thread, Shizzlmah outlined the problems he had with an industrial grade, commercially sourced lathe retrofit kit. Seems the "lathe" version hadn't made a good/adequate transition from being a mill controller.

To summarize:

1. our Australian member preferred to use legacy PC's. Such devices preclude the use of XP needed to run Mach 4.

2. Mach 3 is no longer supported by the creator - they've moved on to XP. Support would have to come from the user group. Whether or not that would be adequate for FVP is something only he could answere - it is not adequate for my needs/operations.

3. Earlier versions of Mach that run on the preferred DOS legacy computers will run mills but will NOT run lathes. That is right from the folks at Mach.

4. Dind't see where TurboCNC (DAKENG.COM) would run a lathe but I didn't shop the whole site. See reasons why this isn't feasible at beginning of this post.

After literally WEEKS of searching, the only proven DOS based CNC system that I could EVER find that would run on legacy mills, lathes and 4 axis VMC's was sold by Bridgeport in the late 90's as part of their DX32 system. It was never offered in the aftermarket in any form.

Unless the member is willing to modify his intended component integration list, he can't do what he wants to do with what he has.

I too would contend that for a big machine like our Australian member has, a servo system would be the better way to go - it would have the speed and torque he will inevitably need.

Balsaman's comments in post #29 regarding the use of servos vs steppers on a big INDUSTRIAL SIZE lathe this size speaks volumes!!! Far cry from what you an get away with on a small/smaller, home size lathe.

balsaman
07-29-2006, 01:48 PM
All versions of Mach software have always only ever worked on Win XP or 2000. There has never been dos versions of Mach software. The original version was called Master 5 and ran on win 95/98 only, never DOS.

Both Mach 3 and Turbocnc can be used on lathes The author of Tcnc originally wrote the software to run his converted lathe. Both have built in single point threading capabilities by using a simple spindle 1 CPR RPM sensor. Both can run multiple axes simultaniously for tapers or whatever (up to 8 axes for Tcnc and 6 for Mach). Mach 3 runs my 3 axis mill all axis simultaniously for 3D contouring. Mach 3 lathe version is called Mach Turn. I have no experience with it but I know it has improved leaps and bounds as of late. I am sure it is not up to the mill level feature wise but I know Art (the author) keeps improving it. Mach 2, 3, and 4 (which is still a beta version) are all currently supported by the author. Master 5 and Mach 1 are no longer supported.

I am not saying the conversion is easy. It's not. But it can (and has) been done. The fellow who started the thread asked some questions about how to do it. I am trying to answer the questions to help him accomplish it in a realistic, cost effective way. Answering the questions by telling him it can't be done does not help. I would have never done anything cool in life had I listened to the nay sayers, and there are plenty of them.

It can be done. It's tough, it takes perseverance, patience, know how, mechanical abilities, imagination, blood, sweat, maybe tears, and some money. But it can be done. I could do it.

Eric

NC Cams
07-29-2006, 03:37 PM
Pursaunt to FVP's post #1

"...But the problem is im (sic) new to electronics and CNC is not my strong point...."

Pursuant to FVP's post #23:

"...a PC or a laptop there are heaps of them around for next to nothing in price
old 486 will run most of the programs out there considering the old very early CNC lathes and mills had very old PC boards in there and functioned OK to a point until you overload the memory space on them LOL..."

Maybe old stuff down under but not Mach

With these givens, and the fact that retrofitting a lathe is clearly NOT A PLUG AND PLAY sor of projet, I'm only trying to point out some realities that the member is going to have to face/deal with

The type of PC's he's talking about simply won't run the XP version of Mach no matter how much as you say "... perseverance, patience, know how, mechanical abilities, imagination, blood, sweat, maybe tears, and some money" that you throw at it.

I dare say it would be nye on impossible to do for a CNC challenged indiviual and if the member is electronically challenged as he admits to being, the retrofit would be even MORE difficult to pull off successfutlly.

In point blank terms:

DON'T use a laptop - per ArturoD's experience.

Do use EXACTLY WHAT MACH recommends with respect to PC, processor, processor speed and memory requirements (forget the salvaged legacy PC idea).

DO USE XP because each and every verssion of MACH that is currently supported runs on that O/S

If you use MACH 3, use whatever Artspoft recomments. Per the Mach FAQ page:

http://www.machsupport.com/artsoft/faq/faq.htm

Looks like you have a choice between XP and (tah dah) XP.

I hope our Australian member finally understands by now that his seemingly enthusiastic plans to bolt together legacy stuff to do CNC machining on the cheap is NOT going to work the way he'd initially hoped to do it.

I am trying to help. I'd contend that telling him in no uncertain terms that it CAN'T be done the way he'd hoped to do it is good, straight forward information that he need to know and recognize before he buys more stuff that simply won't integrate.

If when the member finally realizes that perhaps Mach Turn is what he needs, the Mach experts can support his project as I'm sure they have a want to do.

IMO, I think he'd be better off getting an already converted CNC lathe with a dead controller. The mechanicals would be DONE and the only challenge (AND IT WOULD BE A CHALLENGE) would be the CNC side retrofit. That's enough for ANY newbie, again IMO. The complete retrofitting of a manual lathe to CNC is an extreme case of complecity in search of a need.

balsaman
07-29-2006, 04:24 PM
A 1 Ghz 'puter is a legacy machine.

NC Cams
07-29-2006, 04:32 PM
Then 233mhx Pentiums must be pre-stone age.


IF that's the case, then what are 133's and, God forbid 386 or 486's???? (which still will do a lot of machine controlling and/or spreadsheet or wordprocessing tasks.

balsaman
07-29-2006, 05:38 PM
Pursaunt to FVP's post #1
IMO, I think he'd be better off getting an already converted CNC lathe with a dead controller. The mechanicals would be DONE and the only challenge (AND IT WOULD BE A CHALLENGE) would be the CNC side retrofit. That's enough for ANY newbie, again IMO. The complete retrofitting of a manual lathe to CNC is an extreme case of complecity in search of a need.

On this point you are indeed correct. This is the best way to do it.

E

FPV_GTp
07-29-2006, 09:17 PM
Hi

It is ok guys , as i said before whether it be a bench top lathe or a bench top lathe that will break my back trying to lift it on the bench top what is the difference ?

there both lathes but different size ???

My lathe conversion i don't expect it to be as good as a commercially bought unit but it will definitely be able to perform cnc tasks

"quoting someone's words here I have existing CNC lathes. Simply replacing the controller with a PC based system has not been possible - what it would take to engineer and fit ball screws and drives to a manual lathe aren't easy even if one has an engineering background. "

Whether you mount a ball screw on a small bench lathe or a large lathe like i intend to do , what is the complications there ? I understand its not going to be a straight forward fit .

Will involve some thinking and tricky machine work which is a challenge but like anything else in life i will think hard and smart how to solve the task.

I have machined i think more complicated things in my time. and had great challengers in life.

I said electronics is not my strong point but i'm sure i can learn as i go along.

I know everyone has to start some where and we all have to learn from someone but one thing i have found people that hold a education tittles seem to think there better than everyone else.

A title like electronics engineer and many spin of engineering titles in Australia , most of these guys look down on you and think your no one , they have the attitude of I'm better than you and talk in there own language.

Guys that may be offended here , but that is the truth

I have more than just a 386 laptop LOL , and remember guys PC's are not expensive even new late model units .

Let me have a look on the mach3 site and see what the minimum software and hardware requirements to run mach3.

Like i said im open to any guidance and feedback from anyone , whether i use that advise is another thing.

Yes i am new to CNC and i'm sure i can learn it just like everyone else has.

What is this forum all about and many other forums a processes of sharing information and discussing ideas. A means of communication and a lot of advertising from business.

cheers

FPV_GTp
07-29-2006, 09:33 PM
hi

Just went to artsofts sites and the minimum requirements are as follows

" All of Artsoft Software has been developed around the ArtSoft pulsing driver for Windows. This driver was created for reliable pulsing under Windows environments to eliminate the problems which previously plagued Windows CNC software. It can reliably pulse to 45000 pulses per second in XP and Win2000 configurations. Its list of features grows every month from user requests. Join the support group to add your voice to the growing list of Mach2 and Mach3 users. "


there are a lot of laptops and PC's in XP and Win2000 around that are a year old and very cheap , www.ebay.com.au is fantastic site for buying computers.

even new laptops are cheap with the minimum requirements to run mach3


cheers

NC Cams
07-29-2006, 10:29 PM
Regarding the use of a laptop:

FOR GOODNES SAKE, PLEASE REREAD POST #27 ABOVE.

If/when a laptop causes problems, you won't be able to say you weren't warned by folks who tried to help...

FPV_GTp
07-29-2006, 11:37 PM
FPV,

One last advice; DO NOT USE A LAPTOP FOR RUNNING MACH. I know they look very sexy on the machine, but there are many issues about the hardware, and how battery saving issues messing around with the processor’s speed. Please watch NC CAM’s comments. I am a very happy user of mach and winxp, and I do recommend it, but please do not take it for granted. Follow Art's recommendations on how to set it up, and please, use a dedicated machine. If you find that machine is not reliable with winxp and mach, please do not try to fix it, change the PC. I understand you must balance your budget with the final product you need or want. I think none of us can tell you if you need to buy a compact or a pickup truck. The only thing that you can not play around is safety. Do not attempt to play around pneumatic chucks, tool turrets, and bar feeders unless you know what you are doing. I know the way I say it make it look like wiring all the gadgets is pretty simple, and it is, but if make an error estimating how a relay, solenoid, or valve will behave on a certain circumstance, then you run into safety issues.

Arturo Duncan
http://cnc4pc.com

hi

Ok ,read and understood , Brian cheque is leaving monday to you for mach3

OK laptop idea discarded nothing a nice tool box on wheels and draws painted in a nice machine colour scheme with a big 19 or 20 inch monitor will not fix , get the BIG SEXY LOOK ;)

cheers

balsaman
07-30-2006, 08:59 AM
Who is Brian? I would wait with the purchase and concentrate on the conversion first. The demo can be used to get the machine up and running. The demo is fully functional for up to a 1000 line Gcode file.

E

FPV_GTp
07-30-2006, 10:48 PM
hi

Brian is from artsoft mach3

mach3 is very reasonably priced , its not a big investment at all but seems the go by a lot of the forum uses in here and mach3's forum pages.

"The demo is fully functional for up to a 1000 line Gcode file " understand where you are coming from but this gives me a fully licenced copy and it's mine. I can play around with it , i know i can do it with the demo copy also but why waste time buying it when it seems the software to go with , read there website and features there software has as opposed to more expensive ones arond.

No one has suggested any other reasonably prices softwares that i can afford at this stage , I see even nickname " stevie " in this forum is using it on his gantry milling machine and i imagine even on his lathe.

So this will not break the camels back LOL

Had a look at some nifty tool changes just pondering with the idea so guys don't shoot me yet LOL , that are commercial tool changers here are some pictures , i'm sure some of you guys will recognize the brands.


several questions guys

q1. what is the best ball screw thread pitch for the X-axis ?

q2. what is the best ball screw thread pitch for the Y-axis ?

in thread diameters from 25mm and say 30mm ball screws ??


Another reason i want to use very large stepper motors is i don't need to gear the drives , will be plenty grunt in the stepper motors

Large servo motors are very expensive anyone know of a good cheap source for servo motors ? Found a few sites and still waiting on email replies back.


cheers

NC Cams
07-30-2006, 11:57 PM
You are going to need a BIG any kind of motor to run a lathe of that size. Big steppers are NOT that much if they in fact are cheaper than servos when you get that big.

The servos on my Fanuc 5T's are the smallest ones Fanuc makes - Model 0. Yet, they are the size and weight of a Chevy V-8 starter motor - and they're geared 2:1 to boot.

The comparably sized stepper that I have on a mechanized infeed for my cam grinder is comparably sized (to drive the same weight or nearly the same) and the price is as much or MORE than the Fanuc servo motor. In fact the stepper is more because BIG steppers are rare and thus more pricey.

If you want any resolution, you simply CAN NOT go direct drive. Figure the resolution potential for a 10 rev per inch ball screw, driven at 1:1 with a 2000ppr encoder versus the same screw at 2:1 with same encoder.

Twice the resolution with 2:1 and twice the torque needed to drive the 1:1. And ultimately torque is what moves the carriage and crossfeed. Also, if you direct drive, your current requirements will be HUGE. When you keep current in the 12-15 amp range, you can get away with and can afford Geckos or Rutex.

Start pulling 25-30 amps, you're now talking AMC's (I don't think the make step/direction drives) and these are easily $560 USD each and they don't turn up on EBAY that often.

The ball screws on my Fanuc 5T's are 35 mm in the ball path area OD for BOTH axis. Your choice ultimately but bigger is better and 30's would be the smallest I'd consider.

In the mean time, you might want to reconsider some of the SWAG"s that you've got on your plans list. Do some looking at what comparably sized machines may be using.

If the results of your investigation don't bear out your plans or theories - believe what's working and invent new plans and/or theories.

FPV_GTp
07-31-2006, 08:59 AM
hi

"saturday here in Australia and the big tattslotto draw is on first prize is $20,000,000 will buy one ticket for that draw " back to work again didn't win the big draw

what is a good CAD/CAM program ? remembering budget in mind something that's affordable and i don't have to sell my house

Ok understand when you mention increasing the working power of the stepper motor and or servo motor when using a 2:1 ratio pulley setup.

what have other people done to ratio setups , as in 3:1 , 4:1 and so on ??

the lathe that im converting is not a small benchtop , so putting some sort of pulley and timing belt arrangement will not be a issue , just concerned with the load the timing belt will have any issues driving the cutting tool and slide carriage the ball screw back to the stepper/servo motor. As this is not a small lathe cutting deep might be scarey.

Oil , grease , water , grit and sworf all will affect the rubber constructed timing belt will have some major job just sealing the belts from the harsh environment it has to work in . Since most timing belts are around 25mm wide might have to double up the width 50mm to halve the work load of one belt on its own. Just a thought.

I will most likely will use overhead cam engine camshaft and crankshaft toothed sprockets and timing belts are available in different lengths and very readably available . The timing belts are strong driving the engines camshafts and accessories.

This will be experimental time in the conversion


servo motors are not cheap from what i have seen on the websites. What's a cheap supplier ?



cheers

" don't you hate it when someone buys something for $2-00 and sells it for $2000-00 "

NC Cams
07-31-2006, 09:53 AM
Point of order - rule of law in CNC:

1. Big stuff (motors, drives, etc) are ALL costly

2. Lower volumes (big motors are industrial/limited use) mean higher prices and less likelihood of Ebay cheapness - other people with "real" CNC's need service parts and they have to pay dearly for them.

3. Too wierd of a component hodge podge can put you in a position where finding help can be difficult if not impossible.

4. Matched automotive pulleys for OHC are ALL going to be 2:1 ratios in sets - think about it for a while and it will make sense.

5. Yes, various belt lengths but ALL are very long. My CNC lathe belts are about 1.25" wide and the center to center distances is about 8" or so - real tight package AND well shielded from coolant splashes. Automotive belts are good in quality BUT too long in length - they will NOT survive direct coolant exposure. Wanna do it cheap? think go-cart roller chain drives - bullet proof in compared to ANY belt.

2:1 is the defacto standard reduction factor. Odd ( 3's, 5's etc) as opposed to even ratios (2 or 4) are simply NOT done - do the math and you'll see that odd numbers don't divide well into a number system that is traditionally based on a system that is evenly divisible by 2. Besides, 2000ppr encoders don't take kindly to division by 3 either...

EDIT Besides if you run 4:1 the encoder counts per rev can get so high that the computer can't count them fast enough. This situation gets worse when you try to feed the counts thru the parallel port. NUMERIALLY, anything should be possible, TECHNICALLY it ain't always possible to do that much in what becomes too little time.
END EDIT

Question: have you even looked at/considered what's being used and why or is this a TOTAL start from scratch with a preconcieved SWAG devlopment program???

No problem with creative thinking but it ultimately has to integrate with "traditional CNC engineering and design" concepts. It also needs to be technically viable.

Too much out of the ordinary thinking makes getting help for a "too far out there" new scheme difficult. The "boldy go where no man has gone before" Star Trek approach can ultimately be the undoing of a project.

FPV_GTp
07-31-2006, 10:50 AM
hi

all automotive pulleys are a two to one ratio.

my question was not do engine camshaft and crankshaft pulleys come in different ratios? But has anyone used a 3:1 or 4:1 ratio in pulley arrangement to drive a ball screw via a stepper/servo motor to make the mechanical effort to drive the system easier and higher resolution in steps?

Timing belts come in all types of lengths from 200mm up to 1500mm in linear length , as far as a straight on fit I'm very sure it will be a lucky , but some sort of belt tension arrangement will be required firstly for adjustment and secondly belt stretch maybe a automatic spring loaded tension to keep things nice and firm.

Yes probably a chain and sprocket arrangement would be a better choice. And again you local V8's ford or chevy engines have a nice double row chain and sprocket arrangement " note all engines run a 2:1 ratio " , the chain is very short probably talking about 8 to 9 inches between centers , will measure one at work tomorrow.

I'm very surprised that a PC can be restricted to serial data counting ?

PC's are very fast in number crunching I'm sure there is a limit but we wouldn't be any where near it if use a 4:1 ratio increment increase ???one example is a optical ignition sensor in a nissan VG30ETT V6 engine has a 360 slot wheel and at 7000rpm that's a lot of square waves pulse counting by a 1995 ECU in a vehicle as compared to a PC , and that's not the only signals going into the cars ECU and not to mention data to activate things coming out of the ECU .

Everyone has different ideas other wise all commercial CNC machines would be the same ????

cheers

FPV_GTp
07-31-2006, 10:55 AM
Hi

I failed to mention i seen someone in this forum using 1.8:1 raito connection between the ball screw and stepper motors

I haven't had a look at what is involved with the software to run the cnc setup

I imagine there is fields one can tell the software in the thread pitch and gear ratios and steppers it has to count to control the X and Y axis

lets see how i go here , will be fun

cheers

balsaman
07-31-2006, 11:01 AM
"AMETEK 38VDC 900 RPM MOTOR" about 3/4 down the page in the center would be good candidates for your lathe.

http://www.73.com/a/0082.shtml

Add some 250 CPR encoders and you are good to go. These are very similar to the motors on my mill. Lots of torque. Go 2:1 on 5 TPI screws.

40-50 volt DC powersupply coupled to Gecko 320 or rutex drives.

E

FPV_GTp
07-31-2006, 07:05 PM
hi

Balsaman having a look at that website now , thank you for that info balsaman .

NC Cams do you have a thread or pictures to show on you CNC_LAthe that i can have a look at ?

Ok guys anyone else have a thread on a lathe or mill setup , just post a link in here or even your own website , would love to have a look .

If for some reason you don't want the whole world to look just email me a link or picture or PM via www.cnczone.com

Pictures are worth a 1000 words so guys picture of you latest CNC toy with a brief specification description on the machine.

Another Question for the senior members in here where does one make a donation ? to this site since im using the cyber space time i thought i better contribute some funds for ONE OF THE GREATEST CNC FORUMS i have ever come across.

So much information in here i will be sifting for hours does someone have a direct link to the conation section ?????

cheers

FPV_GTp
07-31-2006, 07:17 PM
hi

Yes you are right , a very nice motors

motor1 -AMETEK 38VDC 900 RPM MOTOR - 900 RPM AMETEK, #965922-101. Permanent magnet DC motor rated 38 VDC nominal. Reversible, ball bearing. Max. rated rpm is 1300 max. Armature current before permanent demagnetization is 12 amps. Torque constant is 50 oz-in per amp. Terminal resistance 20 ohms +-20%. Voltage constant is 37 VDC per 1000 rpm. When tested on 38 VDC, we recorded the following data: No-load spedd 1100 rpm @ 0.260 amp. With a 100 oz-in load the shaft speed was 900 rpm @ 2.3 amps. When tested as a generator at 1000 rpm, the output was 5.8 amps @ 12 VDC. Shaft: 5/8" dia. X 1-5/16" long. The opposite end of the shaft has a turned down diameter and a flat mounting area with two sets of tapped holes. This was probably originally intended for an encoder or tachometer mounting. This shaft has an outside dia. of 3/16" and is approx. 3/8" long. We do not have the encoders whtat were mounted on this motor, but suitable encoders are probably available from encoder suppliers if required. The motor has five #10x32 tpi tapped mounting holes on the shaft end of the motor body. Electrical connections are via 3-1/2" long flexible wires. Dimensions: 4" dia. X 4-1/2" long (excluding shafts). $74.50 Ea. MD548

motor2 - AMETEK 38VDC 900 RPM MOTOR WITH 5/8" DIA. OUTPUT SHAFT - 900 RPM MOTOR AMETEK, #965922-102. Same specifications as our MD548 except the main output shaft is 5/8" dia. And 1-7/8" long. The encoder shaft at the other end of the motor is identical to the one described in the write-up of MD548. Approximately 1500 units available. Weight 7 pounds. $74.50 Ea. MD549

now is just a case of finding some 250 CPR encoders ? any ideas where guys ? will do a yahoo search lets see what i find.

this what i found amongst a lot of other encoders , here is a link

http://s120220635.onlinehome.us/servo-motors.asp

http://www.usdigital.com/products/s1s2/ found a little bit of info EDIVIDE
Integer (Whole Number) Resolutions Available http://www.usdigital.com/products/edivide/integer-resolutions.shtml

converting shaft rotation into electronic pulses, encoders are used to electronically this is a PDF file

www.ab.com/sensors/sensorstoday/pdfs/july03/encoder_sg.pdf#search='250%20CPR%20encoders

and more encoders http://news.thomasnet.com/fullstory/486545



cheers

balsaman
07-31-2006, 07:59 PM
http://www.usdigital.com/products/e2/ These are the ones you want. 250 CPR. Get the 6' cables with integrated connectors with them at the same time.

You will need to dissasemble the motor to add a stub staft to mount the encoder disk.

E

balsaman
07-31-2006, 08:04 PM
http://www.cnczone.com/forums/view.php?pg=donations

NC Cams
07-31-2006, 08:09 PM
Re: lathe photos = I don't own a digital camera.

At one time, I did a "Cadillac NC100 lathe" search on google (my exact machine) and a foto of one with something other than a Fanuc control came up. They are not that popular now as they were a 1979 era machine - I got mine out of "mothballed" close out sale from a shop that had 3 of them.

You might try googling a "Bridgeport Romi 2 or 2S" lathe. These are decent size full CNC lathes made in late 90's with a proprietary Bridgeport DX32 control system - much more common and easy to find.

It will give you a representative picture of a CNC lathe albeit with electric "feed handles" to electrically drive the servos ala what you'd do with a mechanical lathe.

Re: what a NC/CNC lathe looks like: picture a mechanical lathe with a ball screw in place of the lead screw to drive Z.

Instead of a quick change gear box hooked to the lead screw, a servo is mounted in its place. Endoders on opposite end of belt drive. There are NO shift handles and NO manual handles at all on my lathe - it is all servo driven. The "lead screw/ball screw nut is fixed mounted to the carriage for both Z and X..

The cross slided has NO handles nor clutch either. No mechanical infeed at all. Servo is out the back side of the cross slide and is 2:1 connected to the X axis.

The device is "connected" between the spindle, X and Y axis via "wire" ala the servo mounted encoders and a spindle mounted encoder with a 1 pulse per reve "timer pulse" for threading.

If you mess up the encoder count with respect to screw pitch with respect to gearing, you'll perpetually make/cut junk.

Lathes of the size and type you're working with are NOT regularly retrofited to true NC. This is why I suggest you get an NC lathe with a dead control. if you get one that hasn't been picked over, your mechanical side issues may be done for you already.

Some math to consider:

5 revs/inch on screw. 2:1 gearing 250 ppr of motor mounted encoder. For each tick the motor emits, the axis will move 0.000400".

10 revs/inch screw, 2:1 gearing, 2000 ppr of motor mounted encoder. Each tick now only generates only 0.000025" theoretical travel of the axis.

Have you REALLY set down to figure out what you need or are you just buying stuff on price and availability on E-bay??? Is it still a great price if it ultimately doesn't work properly????

Sooner or later, all this stuff needs to be integrated. If you're not careful, you could end up with great deals on stuff that you can't use or ultimately won't work or will be dead slow or gutless.

From a previous poste, you expressed a comment about number crunching in a computer. Here's why PC's sometimes SUCK for CNC as composed to a true, dedicated control thread:

Why parallel ports may sometimes suck at doing CNC control (See post #5 in the following thread):

http://www.cnczone.com/forums/showthread.php?p=181852#post181852

Develop a wrong perception of what a computer does and/or how it does it and you could become extremely disappointed.

balsaman
07-31-2006, 09:42 PM
Actually 250 CPR is 1000 pulses per rev so on a 5 TPI lead screw @ 2:1 ratio you get a resolution of .0001 or 1 thenth of a thou. I guarantee you this is much better resolution that the mechanical parts of the mill will get you, so no need for higher CPR encoders. You don't want 1000 CPR encoders as it takes a very fast PC to make the machine go fast. The Servo/ratio/leadscrew combo I recommend above will get you roughly 100 IPM rapids which is not lightning fast but good for a hobby type lathe. If you want faster rapids you need different servos. I don't recommend going faster than that. Makes crashes even scarier. My mill will do 100 IPM but I set it up for 50 max as it's safer.

E

BobWarfield
07-31-2006, 10:01 PM
One other thought if you like those motors--read this post by Mariss Friemanis and the associated report he has written:

http://finance.groups.yahoo.com/group/geckodrive/message/9088

That's very similar performance to the motor you are looking at claims, verified by someone who knows and is an independent 3rd party, it is brand new, and there is a known formula for what controller will work with it. You'll still want the same encoder Balsaman has mentioned.

It's worth consideration.

Best,

BW

PS Here is a similar sized lathe, BTW, that is basically a manual lathe professionally converted for CNC:

http://www.microkinetics.com/lathe1236/index.htm

It can be done! The specs on that lathe may be of interest in terms of "what worked" in another application.

FPV_GTp
08-01-2006, 08:16 PM
curtisturner - Chip Sweeper - This might be a dumb question
Link - http://www.cnczone.com/forums/showthread.php?p=181852#post181852
This might be a dumb question but here it goes.

What is the real difference between the following 2 (other than price)
PC and a couple of Gecko Drives some Servo's and Mach 3

And

A NC Controller like Fanuc or Allen Bradley

Thanks
Curtis
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

post # 4 NC Cams Master Machinist -
Why parallel ports may sometimes suck at doing CNC control (See post #5 in the following thread):


Mach is a step/direction system and it doesn't close the loop between what the steppers ultiametely do and what they're told to do.

Sort of like driving a car down the street via radio control - do you feel the acceleration in the seat of your pants if you pull the throttel trigger harde??? The radion (computer) tells the motor to speed up and slow down but can't never feel if it did it or not. That's the easiest way to look at it. Even if you use a servo card with Mach, you don't get closed loop feedback to the PC.

Yes the PC sent out a directive via the LPT port but until/unless the error gets too bad, it continues sending out pulses fat dumb and happy until the servo card sees a sufficient error. ONLY then, will the card notify the PC, again that will be recognzed when the next LPT port call occurs. Although the encoder feeds back to the servo card,the card doesn't feed an error back to the PC until/unless it gets too far behind.

In my servo system, the moment the drive faults (over current, no feedback signal, lag singal, whatever) IT STOPS. It doesn't do so many steps, gets so far behind then says, "we have problem, better stop because the problem finally got TOO bad".

Look ahead functions and interpolation (which any computer time so as to look ahead and calculations to happen for it to work), will bring thruput to a crawl. This is especially true depending on how your processor does background calculations and the priority it gives to them.

Instead of interpolation, try doing point to point milling in very, VERY small steps. WE do it on cam profiles and you can't tell that we've got teeny tiny flats on what should be a full radiused surface.If you make 2880 flat cuts to create a circle,you can't tell it after you buff it with 320 then 600 then scotchbrite.

At 360 cuts, the thing looks like a diamond disco ball with all the facets. Sounds like a machine gun when a roller runs along the surface.

We have the ability to do constant surface speed tool path cutting via S speed changes for every single cut point. The RAMDRIVE program in DOS does the look ahead, the controller sends out the code, the servo amp responds and if it does so properly, the cutter keeps mozying right allong. We run real slow (inches per minute and real high spindle speeds cause we're looking for mirror like finish).

Why an it move so slow and smooth at CSS?

Because a 12 bit ANALOG voltage is being sent to the servo amp (in increments of 0.004vdc, +/-10vdc full scale). Between the possibiltity of the stepper hittiing a resonance frequency and or the step function not being sufficient to provide adequate control at small incremental changes, it is possible for the system to hang up or default to a safe mode or the motor starts to "shiver" and that isn't what you want/need.

In your case, you're still dealing with a step funtion. You may have reached the limitation of your stepper motors and/or the limit for a particular step/direction system. Steppers do amazing things. But, they can't be turned into servos no matter how hard you may wish or

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

post #5 - fkaCarel Apprentice

For starters: it's not a dumb question, but you must have the opportunity to look on both sides of the fence. Fanuc etc. are dedicated and embedded controllers. This means that you cannot do much more with it than controlling coordinates on a machine. A PC is an office machine which gives you, in the end, on screen, the sum of 1 + 1.

The advantage of a PC, fast execution of a part of a program or a whole program, disappears if it has to execute the result of a small program. This means: sending pulses to the parallel port in timeslices is crippling. The design is made to send all the data in a stream to the port. A printed page!

A real time processor derives the time from a timer. When the timer is zero or overflows, depending on the type of processor, a new task can be started. For example the generation of one step. When the task is done, the program waits for the next timer interrupt.

I cannot look in the Mach3 software, but it looks like it's pulse delays are generated by a loop. Load a number, decrement by one and exit if the number is zero.

Where the embedded controller can do initialising of new instructions, calculate interpolation and maintain constant velocity in its free time, for the PC everything is overhead. The to decrement number should be, but cannot be adjusted for the specific software action of the moment.

So the easy solution is: buy the fastest PC you can get. The number in the delay loop grows, the overhead is executed faster. This is noise reduction by numbers.

The costly solution is: buy a Fanuc and have a specialised controller.

The crazy solution is: do it yourself and invent new G-codes and new approaches
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@


thanks for that NC Cams Master Machinist

I haven't gone on a wild rampage yet buying parts other the two lathes which were cheap and the 4 ball screw which are a steal at the price i paid.
Just picking peoples brains and asking questions and there experiences when they started to contemplate doing a CNC_lathe conversion

I know where you are coming from and i thank you for your guidance and helpful information.

I have at work PC's that are on automotive test equipment and PC's in the office and have several early to the latest laptops already in my possession . I was just thinking of using a dedicated PC and or laptop just for the lathe itself with no added programs working in the back ground.

That is why i said there are cheap laptops and PC's floating around with wind2000 and winXP , this way the machine will have its own PC not to share with anything else in the workshop

The actual components steppers motors or servo motors , encoder , stepper motor control , servo controller , power supply(s) , software ( mach3 , desktopcnc etc ) and so on, I haven't yet purchased.

I'm hoping i get some guidance here from you experienced people who have already done a conversion lend a hand with your knowledge. The likes of you NC Cams and balsam and BobWarfield and others that have contributed a lot of information to me. Also some of the postings in other threads i have searched in here , there is just a vast amount of information in here it is like a library in here.

The biggest problem in here is find the information, there is a lot to read and that's why i posted this thread , just to bypass some of the information that's out there as it will take me another year to read , i want to commence on the actual lathe conversion.

I followed some threads and looks at how these people tackled the lathe conversions and mill conversions and what i have noticed they started from knowledge factor zero of CNC machines from the hardware to the software component of CNC machining. I have noticed there either using it as a hobby thing , or there in the trade of fitting and turning ( machinists ) which is a trade in Australia , different countries call the trade a different name.

NC Cams your suggest buy a old CNC_lathe is a great idea but most of the bigger lathes are snatched up well before i hear about them being up on the market place . At auctions it just attracts a lot of potential buyers and the machines end up escalating in price when the WAR ON BIDDING COMMENCES . Great for the seller but in the end the buy has paid way to much for the machine they have just out bided 40 other guys.

I have followed several machine when they have come up on auction and i set a reserved price that i would pay and always the prices exceeds my expectations . That is why i have chosen this path a old very ridged copy_lathe to convert , you could call them a CNC-lathe of the very early 1970's era.

So guys any information is appreciated in this thread . Even if there are threads buried away in the archives of this forum and you know the link just cut and paste a direct link to it in this thread please. I have use the search facility in here and tried all sorts of key words and read a lot of threads in the past few months . Like I said this forum is huge and a wealth of information in here.

Possibly one of the worlds best CNC forums , this is my opinion though.

I still am interested in making a donation to the forum for there services , who is the moderator to speak to ? so i can make the contribution.
and guys thanks for your patients with me .

cheers

balsaman
08-01-2006, 09:33 PM
For donations to the zone see post #51 above.

FPV_GTp
08-01-2006, 09:49 PM
hi

thank you balasan , i missed that post my error and thanks

oops :violin: :mad: :violin: :mad: (nuts) :violin: (nuts) :violin:

cheers

FPV_GTp
08-01-2006, 10:00 PM
OK

donation details have been requested , i would prefer to use a bank check ( cheque ) method

so if anyone reading this thread would like to make a donation to this forum the link is as balasan posted in here

donation link http://www.cnczone.com/forums/view.php?pg=donations

cheers

NC Cams
08-02-2006, 01:21 AM
If stuff is so expensive down under, what about importing something in from the USA???

There are tons of machines looking for homes that can be purchased quite readily. I dunno about shipping but maybe all in all, it might be a better go.

As in get something DONE, iron wise, that only needs a controller replant. That was my intent with my lathe retrofit and learned that lathes retros are NOT easy. Knowing the "challenges" alone offered by the PC/controller side, I wouldn't even THINK of retrofiting a manual 1970's gem. BTW, I have a fully functional Fanuc 5T under power you could buy quite reasonably.

My posts may seem hard core and tough but the task at hand is just that. When I was a training engineer, I was that way - hard a$$ed to the students. One day, months later, a former student came back for a sales conference and thanked me for being such a hard a$$. I asked why as I was beyond horrible to them.

His reply, "... yeah you were, but the customers are worse....". And he thanked me for it.... Go figure.

You've chosen a particularly hard task - and one that is not in a stage of mature develoment (I'd contend). Just, don't get overwhelmed. We'll try to help as best we can.

FPV_GTp
08-02-2006, 03:08 AM
hi
LOL NC Cams na you ok , i have to admit in my time i had some hardass teachers but they were all good teachers , some of the students can get out of hand

And your ex pupil is right customers are harder to deal with LOL

Just of the topic from this thread , what is a better controller the maz_control or fanuc_controller ??

I'm under the impression the maz_controller is made by Mitsubishi and is a bastard of a controller when it comes to software ? It is a all in house type of system not PC friendly with other software ???

Does anyone have a site that has information on both controllers ??

what are all the fanuc-controllers that come out from day one right upto now ? anyone have a listing ? I see fanuc is also in china ?

Same as the mazcotroller , what are all the mazcontroller that come out from day one right upto now ?? anyone have a list of them ??

cheers

FPV_GTp
08-02-2006, 03:19 AM
hi

Just surfing the net again ;) come across this software called SURFCAM and one use it and what do they think of it ?

www.surfware.com

cheers

NC Cams
08-02-2006, 06:09 AM
Here is a must read thread that is quite pertinent to your efforts:

Great NC controller thread - NC vs PC’s

http://www.cnczone.com/forums/showthread.php?p=182852#post182852

Speaks volumes about the controller options.

A lot of the dedicated controls (IE: Fanuc, Mazak/Mazatrol, Mitsubishi, etc) are NOT geared to the one-off retrofitters. Fanuc service sucks and what service they do offer is expensive - can't speak for the others. Al the Man has spoken well of Mitsubishi I think but the controller alone is $10K USD or such.

You can buy a turnkey Ezpath PC based CNC lathe on Ebay for numbers like that. Folks who have them speak well of them.

The previously posted thread says a lot about steppers. Seems that the technology is NOT that user friendly for to the DIY'er with regard to servos- HOWEVER that depends on the technology level you're working with.

The once common, still available analog controls (at this point in my level of understanding) are closed loop capable but how "closed loop" is something that I"m learning is NOT quite perfect. Digital drives like those used by Ajax supposedly have neat 'self tune' features but the other aspects of the Ajax have been discussed ad nauseum on the other lathe thread. Halfnutz experiences with Camsoft disuaded me from even considering them.

Servos too have an "error level". This is why a servo has position and velocity feedback. THe PC tells it to move so far and fast and the servo does so albeit a bit slower than the instantaneous instructions - fast but not instantaneously identical. It seems that the faster you ask it to move, the more error it can develop.

Error to a a servo is analagous to lost steps in a stepper - so much is manageable/tolearable. This is why after a multithousand step tool path, you need to check if the servo will find/keep the same 0,0 (not home) origin.

The way to check this is to mill a circle or cut a taper. If the taper isn't skewed and the circle is round, things are going pretty well. IF the taper is skewed and/or the circle is out of round or doesn't meet up without a step, you have problems.

Whereas a Gecko or like stepper driver will stop if the error steps get say 128 behind, the servo amps, too have the same sort of error logic that they respond to. In my Bridgeport system, the speed/direction signal is in the form of a +/-10 vdc full scale analog signal. The motors send back 2 signals - position to the PC and tach to the servo amp.

While monitoring current and voltage, the amp checks to see it the motor is running in proper direction and at proper speed via the tach signal. If not, shutdown. Similar to what steppers do but without the "issues" of having to go thrue parallel port which is also discussed in the previous thread.

THe following thread helps outline the goods and bads of steppers and servos:

http://www.cnczone.com/forums/showthread.php?t=17419

At this point, I'm not convinced that a CNC lathe will cut threads as reliably as a mechanical lathe. You're still "flying by wire" and an electronic gear is NOT as 100% positive as a mechanical one. Yet, they do so very well, usually.

I'll assure you this much, the more you look, the more disillusioned you may become. You'll learn that this CNC lathe thing is no where's near the level of development of a mill or VMC. Ultimately you'll have to decide as to which compromises you're willing to live with. IF you can, go see a system - surely someone in your neck of the woods has done a lathe retrofit. THey can tell you MORE than you'll imagine. Forget what the salesman says, talk to a user.

When I bought my bench lathe from Grizzly, I asked if they had customers in the area. They did and gave me some names. Called one guy and he said "come on over". Spent the evening with him and he went thru the whole deal with me. I bought the same lathe based on the experience both with the seller and this buyer. A person who has a system is the system's best critic and/or spokesman.

RE: my NC lathes:: Mach is out because of the fact I'd have to go to XP and I don't have the funds to buy that much stuff to support this O/S. I too was hoping to use legacy boxes.

The problem there is there are no legacy systems that have a control offering anymore. DOS/PLC's that worked on legacy boxes are gone. Moreover, analog servo drives that were used with these systems are pricely as well. AMC's are about the only ones that will drive my servos and they are nearly $600 each - far cry from the Rutex and even these are not cheap ($325 each if I recall).

Keep researching.

You need to feel comfortable with your decisions. I can probably provide some servo and drive P/N's that I know will work as a matched assy (they are from BOM of a production late 90's cnc lathe).

CAUTION: these will involve either 3 phase AC and/or DC drives. I still haven't learned enough about the AC's. Since I grew up with DC trains and slot cars, I have a natural inclination to go DC servos - God are they expensive. For that matter, so are the comparable sized steppers on some equipment I have. AC's in that size frame ain't cheap either.

Finally FORGET 100" per minute jogs. They are flat dangerous and downright scarey - besides the're useless. 30"-50"per min is plenty and besides, you don't need a power supply that you can arc weld with to drive them. True cutting speeds and spindle power under load are much more critical, especially if you're looking for a good surface finish....

There is no "better control". They all have features and detractions. Some meet your needs and others don't. Guys who were taught on Fagors swear by them. Guys who learned on Fanuc's, ditto. My neighbor has only Haas and he's a 1 man shop with 2 lathes and 3 VMC's. Says a lot for Haas. The service guy was there once in the 4 years I've been in the complex.

Hope the info helps

NC Cams
08-02-2006, 06:15 AM
Re: surfcam lathe: didn't see anything about threading or taper turning.

Looks like all they did was treat a lathe as a VMC with a 4th axis. A lathe is NOT that.

balsaman
08-02-2006, 07:40 AM
Error to a a servo is analagous to lost steps in a stepper - so much is manageable/tolearable. This is why after a multithousand step tool path, you need to check if the servo will find/keep the same 0,0 (not home) origin.

This is incorrect. A servo will have a small error while running but will always catch up when the axis get to it's final destination and stops turning. A stepper that losses steps will never catch up again.

The only was to "loose steps" on a servo system is a bad encoder, or noise in the encoder cables or in the parallel cable. This can be prevented by doing proper shielding. What can also happen is the load on the servo is so high that the "following error" gets beyond a fixed amount and the servo drive faults.

E

fkaCarel
08-02-2006, 07:49 AM
Let's assume that for a mill the servo position errors form a ball around the command position. For every command position, at rest, the mill is somewhere in the ball.

BobWarfield
08-02-2006, 02:54 PM
This is incorrect. A servo will have a small error while running but will always catch up when the axis get to it's final destination and stops turning. A stepper that losses steps will never catch up again.

The only was to "loose steps" on a servo system is a bad encoder, or noise in the encoder cables or in the parallel cable. This can be prevented by doing proper shielding. What can also happen is the load on the servo is so high that the "following error" gets beyond a fixed amount and the servo drive faults.

E

This is absolutely accurate, insofar as it goes, but note that servo following error can lead to innaccuracies in the finished part even though the servo caught up without faulting. The curve that gets cut in the part will be slightly different than what was intended. In this sense, the other poster is also correct to say that following error can be just like lost steps. If the cutter didn't follow the exact path commanded, but it caught up later, you still have an error. There are many examples of this even on high end machines.

For example, consider the "waves" described by Geof in this thread:

http://www.cnczone.com/forums/showthread.php?t=22589

Somewhere I came across a picture on a GE-Fanuc page of a part that had a curve on it that was off by almost 0.1". There was a ruler for scale and a line drawn in to show what it should have been. I think it was part of the sales pitch for the lookahead and interpolation options. I wish I had the link, but their point was that the machine may have to look outside even of the g-code being processed and plan for what's coming next or the sheer inertia and following error that results can lead to some pretty dramatic inaccuracy while the CNC machine still thinks it did the right thing, closed loop and all.

That's on a real nice has VMC with servos. CNC involves MANY approximations to reality.

Best,

BW

balsaman
08-02-2006, 03:28 PM
Let's assume that for a mill the servo position errors form a ball around the command position. For every command position, at rest, the mill is somewhere in the ball.

That is pretty much how it works. If outside the ball is a servo fault, then hopefully you are staying within the ball while running a part. The heavier the load (or bigger the following error for whatever reason) the closer you are to being towards the outside the ball. As the system comes to a rest tho, you should return to very close to the center, since the closer you are to the edge of the ball, the harder (more current) the servo system tries to get back to the center.

The ball for a gecko servo drive setup done properly will have a radius of 10 thou or so. On a mill I imagine 99% of the time you are within 1 thou of the commanded position unless you are making a rapid move (where it doesn't matter). Cutting forces are generally very light on a ball screw fitted milling machine. I imagine cutting forces on a lathe x axis can be quite high. Possibly a higer ratio from servo to ball screw is required here. Since the travel is quite short, the slower rapids won't matter.

E

NC Cams
08-02-2006, 03:53 PM
I wish this thread was in play last summer.

That's when we were going nuts trying to get our Extrak to cut a perfect circle. We ultimately learned that by running R E A L slow feeds, and doing point to point milling at 1/8 deg intervals and a BIG diameter finish cutter, we got good roundness and minimal error. A 0.010 "window" is way too primitive for what we do.

Any way, the whole time we figured that the computer would recall where the 0,0 origin was for the center of the hole we were miling. Close but no cigar. When we got the code working on the 'Trak, we took it to a Haas for speed and potential accuracy reasons. Essentially we were milling an OD profile that had to be concentric to the ID mounting hole.

The Trak could get within a thou or two which was GOOD but not good enough - we were looking for half thou. This is why we tricked out the ballscrews to the level we did. Got circles round to within 0.0003" - as milled!!!.

After porting the code to Haas (Identical to DX32 save for a couple of insignifigant comment lines and tool change codes), we ran it (with real slow feeds which we learned were critical to accuracy on the BPT). The Haas could do half thou to 8 tenths TIR which we could just barely live with.

A CNC ground part is within a few tenths but triple the price and two/three weeks delivery as opposed to 48 hours or so.

If we get a viable lathe retrofit, we're going to try to rough turn a lobe shape into a cam blank. Don't have to be perfect and don't have to be smooth, just a reasonable lobe approximation. We'll tune it up as need be in finish grind. THe trick will be to point the 16 or so lobes in 16 different angular positions. That will be the tough part as will moving X in and out to generate a decent lobe shape.

Essentially we're already doing it in X and Y axis on a mill, should be doable in solely X if we slow down the spindle and can get the X servo to respond quick enough...

Al_The_Man
08-02-2006, 04:08 PM
Servos too have an "error level". This is why a servo has position and velocity feedback. THe PC tells it to move so far and fast and the servo does so albeit a bit slower than the instantaneous instructions - fast but not instantaneously identical.
In my Bridgeport system, the speed/direction signal is in the form of a +/-10 vdc full scale analog signal. The motors send back 2 signals - position to the PC and tach to the servo amp.

At this point, I'm not convinced that a CNC lathe will cut threads as reliably as a mechanical lathe. You're still "flying by wire" and an electronic gear is NOT as 100% positive as a mechanical one.


Now Modern servo's do not use velocity feedback, this was used on earlier systems that did not have the processing power to control the loop by encoder alone, If replacing drives on older systems many like AMC still include a tach option input if needed, but the favoured Torque or current mode is prefered, with the loop closed back to the control via encoder only.

One of the problems of too high a following error is if the servo's are not sized correctly to enable the system to keep within an accepted tolerance, this is part due to them not being sized in order to keep the motor to load inertia within the industry recommended maximum of below 5:1 (10:1 tops).
If I program an installation to keep withing a following error of 200 encoder counts which represents 10 microns, then following error is not usually an issue,
Actually the threading routine on a Lathe, (which is the equivalent to rigid tapping on a mill) , is more efficient because it is usually much faster, I remember the first time I programed a Lathe retrofit and tested the threading at 250"/min. :cool:
This was for the Aerospace industry so I don't think they would have stood for anything less than 100%.
Al.

FPV_GTp
08-03-2006, 01:04 AM
hi

just searching on ebay.com , wooooo there is alot of stuff on there

come across some fanuc servo-motors

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330013577155

fkaCarel
08-03-2006, 06:15 AM
If we get a viable lathe retrofit, we're going to try to rough turn a lobe shape into a cam blank. Don't have to be perfect and don't have to be smooth, just a reasonable lobe approximation. We'll tune it up as need be in finish grind. THe trick will be to point the 16 or so lobes in 16 different angular positions. That will be the tough part as will moving X in and out to generate a decent lobe shape.
Ever considered a mechanical solution for this? As for ultimate: a 1 on 1 driven, splined shaft drive with a multitude of 8 splines, desmo actuated tool. It's only for removing a lot of metal, so there must be a common denominator.

balsaman
08-03-2006, 07:02 AM
hi

just searching on ebay.com , wooooo there is alot of stuff on there

come across some fanuc servo-motors

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330013577155

Can't be driven by Gecko's. Gotta watch what ya get to make sure it's compatible with step and direction type drives.

Eric

FPV_GTp
08-03-2006, 07:24 PM
Hi

Guys some sad news , had just learnt Stevie a cnczone.com forum member has sadly passed away some time this week , spare a thought for Stevie and his family members.

I'm sure his work inspired a lot of members in here . The best machine work i have seen in a long time.

I know i was inspired by his work and i always read his threads , Stevie rest in peace .

My sincere condolence to Stevie's family and friends , Stevie rest in peace mate




Had a look at a small colchester triumph lathe that was converted by a crowd downunder yesterday , nice conversion the lathe is brand new and so is the Bosch controller.

Does anyone recognize the Bosch controller ? and any information on it ?
The machine is sitting in a Machine shop was on loan as a demo to teach students.

The guy told me the controller is playing up and the people that did the conversion have either split partnership or dissolved or gone bust.
He reckons i should be able to get the machine for about $8000

i made a offer of less than what he said cause this guys partner said a different price to what he said ???? PMSFL who's telling the truth ??

and am waiting for a reply back.

Where the machine is sitting they need the workshop space so I'm not sure 100% what is going on there.

Regardless if i get the machine or not i still want to convert my two lathes and a milling machine.

I had a good look at the lathe and took some pictures of the machine , yes the servo motors are big suckers as compared to some of the desktop lathes i have seen converted on the net.

cheers

NC Cams
08-03-2006, 08:09 PM
I dunno about the price but consider this:

1. You'd have hard core, MATCHED TO THE MACHINE SERVOS IN THERE.

2. You'd have hard core MATCHED TO THE MACHINE INDUSTRIAL POWER SUPPLIES IN THERE.

3. you'd have most of the limits and encoders and wiring to same DONE - perhaps they need service but it is easier to copy than to design anew from scratch.

4. You'd have a neat pendant to mount your "whatever" controller into. The rest of the thing should also be CNC ready.

5. You might luck into finding someone who knows/does the Bosch controller. Perhaps you can get it up again for a reasonable sum if it isn't fried too bad - I lucked into such a guy with my Fanuc 5T's.

NOTE: On an old machine, it simply might be loose/corroded wires or cracked PCB. Sometings reseating IC's in sockets, carefully resoldering corrode joints and refurbishing connectors will raise stuff from the dead. Such fixes are CHEAP - and many guys are afraid to mess with control cabinet wiring. How lucky do you feel???

6. You' d have lube, hyd and ball screws/screw drives DONE (and these are ALL major PITA's to do from scratch). You could be looking at closed to $1600 USD to buy ball screw bearings alone for something that big.

7. The all important E-stop circuitry would be done. Even on a retrofit, you'd be simply connecting/reconnecting wires. Running wires alone can take weeks and the conduit connectors etc a pain to source and do. If the wiring isn't butchered, that alone is worth a TON.

8. With that sexy green paint (in nice shape too) you can call it Kermit - as in Kermit the frog from the Muppets.

Pray on the life of those you hold most dear that they have schematics for it or you can get them SOMEPLACE.

WIth schematics, you can readily fix quite a bit with a VOM and common sense. WIthout it, you're flying blind. Major PITA to reverse engineer a full wiring schematic and/or a ladder logic thru a bazillion relays without a schematic to go by.

With schematics, I'd tackle a rebop of this gem -without, I don't know, probably not. I simply wouldn't tackle a retrofit of manual to CNC as you initially planned - you're far braver than I if you do.

If you go this route, everything you learnd here PLUS whatever you picked up the lather retrofit thread I started pertains in spades....

Al_The_Man
08-03-2006, 08:38 PM
nice conversion the lathe is brand new and so is the Bosch controller.

Does anyone recognize the Bosch controller ? and any information on it ?
The machine is sitting in a Machine shop was on loan as a demo to teach students.

The guy told me the controller is playing up and the people that did the conversion have either slip partnership or dissolved or gone bust.
He reckons i should be able to get the machine for about $8000

Where the machine is sitting they need the workshop space so I'm not sure 100% what is going on there.

Regardless if i get the machine or not i still want to convert my two lathes and a milling machine.
yes the servo motors are big suckers as compared to some of the desktop lathes i have seen converted on the net.

The going price depends alot on if the lathe can be demo's in perfect working order, if this is not so then you don't know what you are getting into with a controller that you may find supports hard to get.
The company Bosch has a good reputation in Hydraulics, I saw a lathe of theirs that was CNC but Hydraulic cylinders and scales, no servo motors.
If that is a new control, I find it strange that they used DC servo's, They look like Gettys knock-offs.
You have to find out if proprietary software & cost-of if any is needed to complete the Machine interface PMC/PLC.
Companies like Fanuc charge big time for software and programming unit.
Al.

NC Cams
08-03-2006, 08:57 PM
Googled "Bosch Alpha 2, and 3" as well as "Bosche CC100, 200, & 300". All are early to late 80's CNC controls - seem to pretty popular in Europe. No pictures though to identify exactly what you have.

I'd think you cound find SOMETHING on it via the internet...

Any "fix er uppper" is going to have challenges but even if the control is dead, there's lots of stuff there to work with that's already engineered...

Al_The_Man
08-03-2006, 09:14 PM
Apparently Bosch is now part of the Rexroth-Bosch group.
Al.

Quote:
With its ultra-compact IndraMotion MTXcompact, Bosch Rexroth introduced at EMO a sophisticated controller-based CNC control system for up to 8 axes in two channels.

The drive and control manufacturer is thus extending its open IndraMotion family with an economic solution for small CNC machines, network control systems in transfer machines as well as handling modules.
* About Bosch Rexroth - Bosch Rexroth, part of the Bosch Group, achieved sales of approximately EUR 4.1 billion in 2004 with 26,400 employees.

FPV_GTp
08-04-2006, 03:48 AM
hi

OK , had a look on rutex website and spoke to the Australian guy from rutex servo drivers they are located in NSW Australia http://www.rutex.com/home/index not badly priced goodies.

A bit dearer than gecko but the rutex drivers seems they can handle more powered motors.

now question have opened small stepper motors like idle stepper motors of car and stepper motors out of HP printers but never had the privilege to open a servo motor and have had a look inside

Judging from all the information i have read , electric motor come in a variety of forms from DC Motors , Brushless DC Motors , Servo Motors , Brushed DC Servo Motors , Brushless AC Servo Motors , Stepper Motors and Linear Motors

link Detailed Description of Motor Types -
http://www.motorsoftmotors.com/detailed_description_of_motor_ty.htm#STEPPER

My questions are ?

Q1.One can put a encoder on the back of a stepper motor ? cause in affect a Brushless DC Servo Motors is a stepper motor with a encoder ?? YES or NO ?

Q2. Is it wise to use a Brushed DC Servo Motors ? as brushes wear im thinking in a safety point aspect here and you know how temperamental a motor can be when the brushes get low ????

Has anyone got any pictures of a servo motor that is used in CNC application , I mean a exploded view picture to see the internals of one ???

cheers

NC Cams
08-04-2006, 08:01 AM
DC Servo is a precision, high armature pole count DC motor with:

a. encoder for position f/b
b. tachometer for speed f/b.

Yes, Rogers machine has board to interface with encoders to give more f/b for step/direction steppers BUT adding encoders to steppers is essentially trying turn a stepper into a psuedo servo.

Keep in mind that lathe retrofits are not at quite the level of popularity and dare I say level of development as say mill retrofits. Moreover, for whatever reason (complexity and interest I suppose), servo based system retrofits just aren't done outside of Ajax/Centroid or others as cited in the other lathe retrofit thread

Anilam is not often mentioned as it is predominantly an industrial control. It is the maker of Millpower, the current CNC on the Hardinge/Bridgeport CNC mill. It is a high end DOS based control using TOTALLY proprietary code and hardware. You can buy a kit but I'm pretty sure it is pricey.

A very common method of controlling servo drives that was and is still used in high end machines is via +/-10v analog signal. This provided simultaneous speed and direction commands. You have to create a D-A converter on a board someplace (usually 10-12 bit) to get adequate resolution in your OUTGOING speed/direction signal from the PC or NC controller. You also have to compare that signal some how (usally done in the drive).

Between the speed and encoder feedback, you not only tell the servo where to go and how fast, the servo tells you if it is going there and if it got there but you do it the whole time while doing so.

The stepper merely is told where to go and how fast, the computer doesn't know if it really got three unless you 'close the loop' with f/b somehow. Most step/direction based drives don't close the loop

The last PC based system I found that used analog servo control was the BMDC used in the Bridgeport DX32 system. It ran via ISA bus on DOS 6.22. The board ran up to 4 axis plus spindle speed and could also do tool changing and other stufff. It ran a mill, lathe, VMC and/or surface grinder, depending on software.

It interfaced with industry standard "industrial drives" ala those from Motion Science (DC drives, now CMC), Yaskawa (AC drives) and should work today with Advanced Machine Control (both AC and DC if I recall).

I didn't find any analog board offerd by Gecko/Rutex et al that would work with this type of analog drive but I could be wrong. More importantly, I found no load and run machine control software that would work with any analog boards that are still available today for PCI or ISA slot PC's.

Great. BMDC used a DOS 6.22 PC, industry standard drives, you could probably probably still buy the software from Hardinge-Bridgeport. Where do i get one?? Sadly, you can't. There's NO aftermarket support WHATSOEVER for the board. From what I know the guys who would know how it works are spoken for with other projects and can't/won't provide the needed support.

Moreover, if you try to buy stuff to experiment and the factory authorized repair agent wants a machine serial number and the deed to your HOUSE for the parts. Or they want a used board in exchange. This would indicated that they do NOT want to be bothered with DIY retrofits.

Have you taken the time to read the following threads??? Many of your questions are or will be answered therein:

http://www.cnczone.com/forums/showthread.php?t=17419

http://www.cnczone.com/forums/showthread.php?t=20927

http://www.cnczone.com/forums/showthread.php?p=181852#post181852

EDIT
DC brushed motors are still used and manufactured albeit not as much as the newer brushless stuff. All my Fanuc 5T's have brushed servos as does my Bridgeport Eztrak Mill. The mill had over 10 years use on it before we serviced the motors.

The lathes are like new but have been mothballed for a long time. They were new in 1978 and said motors are still used in MANY circles.

Many high end machines used brushed motors and these were designed for production use. Yes, brushless have their benefits - they also have their liabilities. I would not be afraid to use brushed DC motors today, in fact I am....

END EDIT

Al_The_Man
08-04-2006, 08:20 AM
The last PC based system I found that used analog servo control was the BMDC used in the Bridgeport DX32 system. It ran via ISA bus on DOS 6.22. The board ran up to 4 axis plus spindle speed and could also do tool changing and other stufff. It ran a mill, lathe, VMC and/or surface grinder, depending on software.


Don't forget Camsoft (Galil), Acroloop, Delta-Tau, all 8 axis PC based and offer ±10v analogue control.
Al.

NC Cams
08-04-2006, 08:46 AM
Thanks Al for the reminder.

Galil (Camsoft) was one of those dealt with in the other thread. I 'm pretty sure it was Halfnutz who had "issues" with their system on a lathe.

I haven't looked into Delta-Tau or Acroloop but will.

FPV_GTp
08-04-2006, 08:36 PM
ok
Guys the way i will work on this little project is mount some stepper motors on this lathe in its normal form.

Use mach2

will not use ball screws at this stage just will run it in its normal form , the y-axis is on a rack and pinion setup and the x-axis is on a acme thread .

Yes the old copy lathe has some play and backlash in all areas will tackle that in stages , but mach2 has features that allows compensating for back lash.

Before i invest money in this machine i will just get her working in this form and just perform simple task with her. Ok i know it sounds disgusting guys i mean the lathe .
I will just assume this is just a project at this stage like a lot of small desktop cnc lathes guys have converted.

and like i said at the start of this thread , im not expecting huge miracles and the accuracy is not the issue at this early stage of the project. Cause some time next year it is on the draw cards i will buy a commercial CNC-lathe and a CNC-milling center.

After going to a friends work place and seeing the machines he operating 3 Okuma machine , two lathes and one milling center i have decided i want them in my workshop

another one of my friends who is into woodworks likes my lathe idea and he said once i finish he will be interested in the lathe if i decide to sell her. His constantly manually turning legs for tables and chairs from his timber hobby shop on his farming property.
It looks like i will go with this setup http://www.lowcostcncretrofits.com/Australia.html
and add on as i get better and progress stage by stage.

I did my sums and if i buy this of that guy that of this guy and all the mucking around i'm better of play a little more and just buy the kit of on guy . I know i will get shot now saying this BUT IT IS ALL PLUG AND PLAY lol. ;)

does anyone have a a working demo version of TurboCad or can anyone mention another 2D software that is similar to it. I went to there website but there downlaod is on a 15 day lockout , which will take me more than 15 days to try and master it.

cheers

FPV_GTp
08-04-2006, 10:23 PM
HI

ok just did a few measurements and the backlash is very minimal

the y-axis feed one full turn of the handle made the bed travel 1.29 inches

the x-axis feed one full turn of the handle made the tool bed slide travel 0.200 inches

direct couple some stepper motors with double end shafts and fit the handles back onto the machine witch will still enable me to use it manually

so some 1000 oz in plus stepper motors will do the trick

cheers

FPV_GTp
08-09-2006, 08:48 AM
hi

OK come across a few nice websites

this one is very nice a 7x14 Mini Lathe Tool Changer Controller , so same method can be employed on a bigger lathe the link is and he makes a few other components also http://www.homanndesigns.com/ToolChangerProject.html

come across some nice motherboards for using Gecko driivers here is a link

http://www.pmdx.com/

and this is some awsome CNC software
(Convert your PC to a 6 axis CNC controller for $159 ) link is http://www.machsupport.com/artsoft/index/index.htm

MMMMMMMMM now this is more interesting a conversion

cheers

balsaman
08-09-2006, 02:15 PM
You need to drive the lead screw for the z axis, not the handle. You will need the half nut engaged when in cnc mode.

FPV_GTp
08-10-2006, 12:32 AM
You need to drive the lead screw for the z axis, not the handle. You will need the half nut engaged when in cnc mode.

Hi

Ok understand what you mean drive the lead screw on the y-axis but this is a old copy lathe it has a rack and pinion setup no leadscrew at all on this lathe on the y-axis

It is geared 2:1 ratio rack and pinion that used to be hydraulically with limiter micro switches

all the feeds were electric over hydraulic

so in my case i would have to connect the stepper and/or servo on the crank handle

cheers

NC Cams
08-10-2006, 01:19 AM
Keep in mind that backlash will be a real PITA problem with a rack and pinion.

Unless you find a way to take out ANY gear backlash (which probably won't be even on a well used R&P) don't think that "electronic backlash comp" will work nor work consistently - especially if you're working in the "aceptable backlash zone" of any gear train. IT will worsen if localized wear is unequal.

One of many reasons why converting manual lathes to CNC can prove to be challenging. There's more little gotcha's like this in store for you if you go down this path.

THis is another reason why ball screws are used for ultimate accuracy on lathes.

balsaman
08-10-2006, 01:20 AM
It won't have very good resolution if you drive the handwheel directly. I don't think that will work. at the very least you need to include some gear reduction. The best way would be to fit the axis with a lead screw of some kind if you can.

BTW, the two axis on a lathe are x and z. z being the carriage travel, x being the cross slide. There is no y axis on a lathe. Just a technicality...:)

E

FPV_GTp
08-10-2006, 05:08 AM
It won't have very good resolution if you drive the handwheel directly. I don't think that will work. at the very least you need to include some gear reduction. The best way would be to fit the axis with a lead screw of some kind if you can.

BTW, the two axis on a lathe are x and z. z being the carriage travel, x being the cross slide. There is no y axis on a lathe. Just a technicality...:)

E

LOL Balsaman :cheers:

no problems on the xyz abc ;)

lets see what happens once i wire things up and juts do a test run

nothing a pully system will not fix

cheers

FPV_GTp
08-12-2006, 09:23 PM
hi

All the Milling machines ( or most ) that i have seen converted to CNC run some form of a Laptop Interesting ???

have a look at this site they manufacture longer travels for the X3 mill

they even make a larger table if my memory serves me right http://www.a2zcnc.com/



here is some great sites to visit also on the artsofts.com link page

http://www.machsupport.com/artsoft/links/links.htm

I will be converting a mill , lathe and plasma table soon also just trying to gather more information .

cheers

NC Cams
08-12-2006, 11:19 PM
Re: backlash and backlash compensation = Just because an operating system has a means for backlash compensaiion that does NOT mean that the software will eliminate it as a problem.

If you have a R&P and have uneven wear in the pinion, whatever comp you apply for one area will not apply for another with more or less wear. Backlash can be an ugly thing to have to deal with.

The backlash comp also runs into problems when you do real slow direction changes. Depending on the logic, the comp can get "fooled" on some moves that occur. If for some reason you have to dither (quick back and forth move), you could affect a size change because the comp stacks up although you really don't need all the net comp that your controller applied.

RE: use of laptops = Some laptops have low power LPT ports. These don't work on a 5 volt logic, they work on 3.75 or something like that. Guys have gone nuts with these especially if they don't know about the low vs std voltage systems. Worst of all, it can be an intermittant deal as opposed to a work/won't work situation.

Another laptop problem involves that of battery managment strategies that the machines may incorportate. They can cause the processor or the hard drive to go into low power mode right when you don't want/need them to.

My laptop does bizarre things at strange times when it sits for a few minutes and I only use it to access the net while traveling. God forbid what it would do while trying to control a machine - and I have a very basic Win98se O/S in it which is a pretty mature, "trouble free" system.

Use a laptop if you wish - experienced integrators have advised against it. Caveat emptor.

FPV_GTp
08-13-2006, 05:31 AM
hi

" RE: use of laptops = Some laptops have low power LPT ports. These don't work on a 5 volt logic, they work on 3.75 or something like that. Guys have gone nuts with these especially if they don't know about the low vs std voltage systems. Worst of all, it can be an intermittant deal as opposed to a work/won't work situation. "

hi

yes people have to be aware about the LPT port voltage differances , even if one has a lower voltage output of 3.75V there are voltage regulaters that some people have designed for CNC application

cheers

NC Cams
08-13-2006, 10:11 AM
RE: "...even if one has a lower voltage output of 3.75V there are voltage regulaters that some people have designed for CNC application..." Frankly, I don't see how an external voltage regulator will address this.

Reason: the low voltage is endemic to the operation of the laptop. It is part of the "low power" aspect of it's design and/or operation. Since the 3.75 (or whatever) voltage is a function of the internal bus of the laptop, how would a regulator (assumed to be external) fix this???

I doubt that people go in and start reconfiguring the board components on the laptop to do this - hardly an easy thing to do...

NOW, if you're talking about a "level shift ciruit". This is an externally viable circuit were upon a low voltage signal input IS recognized and a TTL 5vdc level output it it's place. That sort of deal is understandable and it could easily be done on an appropriately configured BOB (break out board).

Level shift and voltage regulator are entirely different things and should not be used interchangeably....

FPV_GTp
08-13-2006, 06:13 PM
"Level shift and voltage regulator are entirely different things and should not be used interchangeably...."

hi

i stand corrected with my choice of words .

like i said at the start of this thread and many postings scatted around forums and this one im new to electronics and CNC.

It is a external " LEVEL SHIFT " fix not a internal motherboard orientation change
and i didn't say people fix the PC or laptops internal electronics or did i

cheers


PS My biggest problem im having is the BULL**** that comes with sales pitchers my product is better than there product , so im weighing up all the pros and cons that comes with CNC conversion

AND not to mention the lots of dealers that re-sell other peoples products at a over inflated prices nothing worse than something passing through 10 sets of hands and something that RRP is $1-oo and becomes $100-oo. What i have come across is people reselling other peoples products and claiming it is there own design and the justifications on there charges.

I believe in a honest day work for a honest day pay

cheers once again

balsaman
08-13-2006, 11:06 PM
Some laptops are fine, others are not. If you want to go laptop, find out what laptops are working for others.

E

FPV_GTp
08-13-2006, 11:58 PM
hi

NCcad i thought i would cut and paste some of the helpful info you posted in another thread in here

for my benifit and others who may read this posting

04-18-2006, 08:28 AM
NC Cams
Master Machinist Join Date: Dec 2005
Location: USA
Posts: 1,378

Part of the learning process should involve how to ask a question.

You asked, "...Where can I get Detailed information on not how to build a cnc machine..." yet you didn't even mention what kind of machine you were talking about until the 2nd or 3rd post.

Yet, EACH of the references cited in my a prior post could have been found using the google/teoma search methods suggested. Your generic unspecific and undetailed question got a response in-kind - no more, no less.

Besides, I was trying to stimulate replies from other members with specific experise in the varous areas you'll need to have help with.

By the way, I found this website and became a contributing "smart a$$" member thereof by using the EXACT SAME search google/teoma search method I proposed earlier.

Ask better questions and perhaps, maybe, you'll get better and more custom specific and detailed answers.

In the mean time, you may find the following to be of help (by the way, most of which were found using the searh function found/contained on THIS website):

Daisychaining ATX power supplies:

http://www.cnczone.com/forums/showt...2015#post142015
http://forums.bit-tech.net/showthread.php?t=108208

Linear P/S design/construction
http://www.campbelldesigns.com/file...pply-part-1.pdf


Bearing literature:
http://www.bardenbearings.com/literatr.htm

http://www.timken.com/products/bearings/catalogs/

http://www.jp.nsk.com/app01/en/cata...cgi?ec=bearings

Get the NSK E1102 catalog for starters

Motor torque info/defininition
http://www.merkle-korff.com/formulas.asp#con

What gage wire to use:
http://www.cnczone.com/forums/showthread.php?t=17350
http://www.cnczone.com/forums/showt...6480#post136480

Servo vs Stepper:
http://www.cnczone.com/forums/showthread.php?t=17419

Simply stepper info:
http://www.parkermotion.com/catalog/catalogA/A12.pdf

Stepper reverse engineering:
http://www.doc.ic.ac.uk/~ih/doc/stepper/others/

Stepper sizing:
http://www.cnczone.com/forums/showthread.php?t=17707

Small stepper P/S
http://www.campbelldesigns.com/file...pply-part-1.pdf



and more



#4 08-08-2006, 05:19 PM
NC Cams
Master Machinist Join Date: Dec 2005
Location: USA
Posts: 1,378

You might be able to DIY the mechanicals but what about the software???

I"d first look at the software that will support a DIY system and then use whatever componentry that they recommend. If you don't do this, you could end up buying something that is not integrateable.

If you're not confused now, keep looking, you will be.

Here are a few links you just might find helpful:

Great NC controller thread - NC vs PC’s
http://www.cnczone.com/forums/showt...2852#post182852

Lathe retrofits (real good buy vs build info)
http://www.cnczone.com/forums/showt...=lathe+retrofit
http://www.cnczone.com/forums/showt...=lathe+retrofit
http://www.cnczone.com/forums/showt...=lathe+retrofit

Research (how to - most people don't know how)
http://www.cnczone.com/forums/showt...99&page=1&pp=15
specifically post #15

Electronics books (buy them if you don't know electronics)
http://www.forrestmims.com
or
http://www.amazon.com/gp/product/pr...glance&n=283155

The "holy grail" of electronics info for the DIY CNC neophyte:
http://www.amazon.com/gp/product/05...glance&n=283155

Web-based books on electronics:
www.ibiblio.org/obp/electricCircuits/

Why parallel ports may sometimes suck at doing CNC control::

See post #5 in the following thread:
http://www.cnczone.com/forums/showt...1852#post181852

Linear scales;
http://www.practicalmachinist.com/c...13;t=003181;p=0

Ball screw basics:
http://www.cnczone.com/forums/showthread.php?t=20748

Ball screw treatise, the hard core stuff:
http://www.cnczone.com/forums/showt...p?t=8813&page=1

PID tuning (for servos)
http://www.cnczone.com/forums/showthread.php?t=20927

Daisychaining ATX power supplies:

http://www.cnczone.com/forums/showt...2015#post142015
http://forums.bit-tech.net/showthread.php?t=108208

Linear P/S design/construction
http://www.campbelldesigns.com/file...pply-part-1.pdf

How to properly phase a transformer in linear p/s:
http://cnczone.com/forums/showthread.php?t=14821&page1

Servo amp P/S design
http://www.elecdesign.com/Articles/.../7635/7635.html

Servo motor , servo amp, powersupply sizing for CNC
http://www.rutex.com/pdf/Mystique2.pdf

Bearing literature:
http://www.bardenbearings.com/literatr.htm
http://www.timken.com/products/bearings/catalogs/
http://www.jp.nsk.com/app01/en/cata...cgi?ec=bearings

Get the NSK E1102 catalog for starters

Press fits:
http://www.eng-tips.com/faqs.cfm?fid=1230

Motor torque info/defininition
http://www.merkle-korff.com/formulas.asp#con

What gage wire to use:
http://www.cnczone.com/forums/showthread.php?t=17350
http://www.cnczone.com/forums/showt...6480#post136480

Servo vs Stepper (READ THIS!!!!!!!!!!!!!):
http://www.cnczone.com/forums/showthread.php?t=17419

Simply stepper info:
http://www.parkermotion.com/catalog/catalogA/A12.pdf

Stepper reverse engineering:
http://www.doc.ic.ac.uk/~ih/doc/stepper/others/

Stepper sizing:
http://www.cnczone.com/forums/showthread.php?t=17707

Small stepper P/S
http://www.campbelldesigns.com/file...pply-part-1.pdf

G code parts counter
http://www.cnczone.com/forums/showthread.php?t=22223

Haas TNC explanation
http://www.haascnc.com/customer_ser...the/96-8700.pdf

Finally, probably a majority of the DIY stuff is stepper oriented. Conversely, a preominant majority of the commercial machine tools that are "factory built" consist of servo based systems.

THERE ARE LIMITATIONS/ADVANTAGES TO BOTH.

hi if i have infringed on any copy rights let me know can delete it all
cheers

NC Cams
08-14-2006, 12:14 AM
There are no copyrights infringed in your post. I'm honored (I think) that you find my postings to be worthy of saving and reposting.

Re: the "voltage regulator" vs "level shift" thingie = people tend to "read in" any number of things into a posting.

For a person familiar with parallel ports, the only ways I"d know of to change the output volatage of the LPT port would be to either go in and somehow change the volatage level on the LPT drivers to 5v or externally create a "level shift" circuit.

THis won't fix any "issues" that battery managment programs running in background may have on the laptops operation with CNC. Post #95 speaks VOLUMES - follow the recomendation posted therein if you go the laptop route. I wouldn't try to reinvent the wheel, life is too short....

I chose the method I did to both explain what a level shift circuit was as well as to dispell the false impression that could be gotten (I got a false impression so others may too) re: changing the output voltage level of a printer port. My style decided upon at the time - no more no less.

Lots of misinterpetations of technology can become "sage wisdom" "psued fact" via repetition on message boards. By being a stickler for the right useage of terms, I'm merely trying to raise the overall education level of the readers of those who may gain some guidance from my posts. Why? It is easy to be educated and sound dumb if you use terms improperly. You'd be amazed at how educated you may sound to an expert if you don't know squat but at least talk in the correct terms.

balsaman
08-14-2006, 09:42 AM
I am pretty sure all the power saving features of any laptop can be disabled, so this is not really the issue. The issue is the LPT port voltage levels. Some laptops are OK, some are not. Some can be fixed by using a breakout board with opto isolated inputs and outputs.

I really think worrying about what type of computer to use is putting the cart before the horse. Get the thing working mechanically.

E

NC Cams
08-14-2006, 10:12 AM
Balsaman: I'd concur with that statement but with a caveat.

There have been any number of cases where systems don't work for any number of reasons. Guys have changed BOB's, motors, rewired, etc only to find low power LPT ports to be the nemesis.

Or the case where things work fine but then go to trash when computer hiccups. Go thru a thrash and come to find it is a laptop or some other device with an energy saver or a darn screen save that is causing hiccups.

There are times when the poor neophyte reinvents the wheel - I'd contend un-necessarily. I'd like to think that the best advice for a nooby is to both tell them what to do and what NOT to do. Veterans know about the issues that have cropped up. Nooby's don't. It is our duty to advise them of that too, no???

Why reinflict the misery???

Maybe a "nooby do/don't list" for starter systems would be nice. Not a detailed construction list by any means. But merely a categorizing of the dumb, irritating things that need to be addressed/considered that we've all found as we've traversed the minefields of DIY CNC.

balsaman
08-14-2006, 12:30 PM
yep.

Of course, to add to the puzzle, some desktops don't work either. I have heard IBM's are the worst, laptops or desktops. Toshiba laptops seem to work the best. Most clone desktops are fine. My advice is to build the thing. Get a computer and try to make it go. If it does't go properly, try a different computer before trying anything else, even if it means carrying the computer out of your office to the shop for testing purposes.

Really, sorting out the computer this is one of the easy parts if you use your head. The mechanicals are the hard part, and the part you should be concentrating on. (The CAM part is also pretty hard for most folks, but that's later).

My advice is still as follows, take it or leave it (at your own peril):

Don't use steppers, use brushed DC servos.

Don't hook it up to the existing rack and pinion. If you need to save money and just wan't to get it going, add an acme lead screw to the x axis at a bare minumum.

The machine will have backlash which you will hate, but it will go under it's own power and cut parts. Backlash comp, while it seems like it will fix your problem, will not. It helps but BL still sucks, even if it's the same amount of BL all over the machine. I know because I had about .006" in mt ballscrew fiitted mill and I ended up adding more ball nuts to make preloaded nuts to eliminate it.

Using the existing rack will not work. The resolution will suck, the stepper won't have enough torque, especially if it's not geared down. You need to aim for .001" per full step, preferably better. 200 step steppers at 1:1 and 5 TPI lead screws gets you .001" per full step.

E

NC Cams
08-14-2006, 01:09 PM
The unbridled FACT of the matter is that there were hundreds of CNC lathes built over the years with DC servos. Fanuc and Bridgeport come to immediate mind.

They work, they run, they have rip the tool in half torque (forget lost steps) and they don't have resonance problems to face/dodge/deal with. They do have others but at least they are tuneable.

Amazingly enough, even though servo's are supported by Rutex and Gecko et al, folks still seem hell bent on using steppers - in spite of the issues that they face/will face with them.

Why? Probably because they are simply cheaper and easiery to "plug and play" with(sorry had to use it -there is NO P&P in CNC) than servos. This is probably why I suspect the users gravitate to them.

You can readlily size a servo by simply matching the specs of a known servo on a known funtional CNC lathe/mill. For whatever reason, some would rather reinvent their own wheel and enjoy the grief, er sorry, challenges that go along with integration engineering one's own system from scratch.

Frankly, life is too short and why not use someone else's engineering knowledge to essentially duplicate a functioning PROFESSIONALLY ENGINEERED system. If you're going to cheat on the engineering test, cheat from an expert's paper.

More FWIW: research I did on my lathe retrofit found that a MINIMUM DC servo motor needed to drive the X axis on small to medium size CNC lathe needs to have at least 14lb-in torque rating and be capable of 3100 rpm at 100vdc. The Z axis needs to have 28 lb-in at same speed and RPM. Both are driven at 2:1 with ball screws. That is some OOMPH and you'd need more (double the torque @ half the RPM) if you tried to 1:1 drive the beast as it was suggested the intent might be. That much torque/current is going to severely tax the current capability of ANY servo or stepper amp.

I'd make sure that if you go to steppers, you have at least that much torque to avoid step loss problems at high modes of acceleration asked for on either axis. Better yet, go with servos - once you figure them out, you won't go back to steppers. I have both and the ONLY reason I don't mess w/ the stepper is that it's a dedicated special 1 axis system that simply is NOT worth converting to servos.

FPV_GTp
08-21-2006, 08:27 AM
hi
hi


Heaps of Fanuc servo motors on ebay and some nice sizes 1 to 2 plus horse power AC and DC servo motors with big grunt

Is there a any cheap controller that will allow the fanuc servos to be coupled upto a PC and use mach3.

a few examples from ebay.com

http://cgi.ebay.com.au/FANUC-AC-SERVO-MOTOR-20F-2000-A06B-0536-B755_W0QQitemZ250019171198QQihZ015QQcategoryZ78195QQssPageNameZWD2VQQrdZ1QQcmdZViewItem#ebayphotohosting


this is a big sucker http://cgi.ebay.com.au/Fanuc-A06B-0512-B254-Model-5-AC-Servo-Motor-Remanned_W0QQitemZ110022416036QQihZ001QQcategoryZ78195QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

found this on this forum http://www.skyko.com/products/

will enter there forum and ask the same question there

cheers

Al_The_Man
08-21-2006, 09:22 AM
The Fanuc redcap motors are AC. (yellow DC) Fanuc uses a different way of commutation, there was a poster here who was reverse engineering the method and coming up with a drive, I am not sure how that worked out.
Al.

NC Cams
08-21-2006, 09:36 AM
The Fanuc DC servos I'm familiar with can only be driven with the DIY style servo drives supplied by Rutex. Reason: the Rutex's are the only aftermarket/DIY grade servo amps that have the volatage and current ratings suitable for the "big grunt" Fanuc's.

The Skyko product should take step and direction signals from a Mach and turn it into the +/-10vdc analog signal needed to signal an analog servo drive/drive for DC servo motors.

With the Skyko, you'd still need a servo amp (IE: Motion Science, AMC, Siemens or other analog DC servo motor drive) to drive the motor.

Perhaps a simpler way would be to use the Rutex as they go from S/D signals right to the ability to drive the motor.

EDIT:

If you are Fanuc parts shopping, DC servo motor Model 0's at 2:1 drive ratio on 90-100vdc are adequate for both X and Z for a small to medium size CNC lathes.

For larger lathes, Model 0's on the X and Model 5's on the Z should be adequate. IMO, Model 5's might be overkill on the X axis.

END EDIT

FPV_GTp
08-21-2006, 07:11 PM
Hi

Rutex has no previssions for thread cutting , i already spoke to Australian guy here in Sydney

cheers

dvsU12
08-23-2006, 01:41 AM
hi

Bought another center lathe with gap bed and a 3 meter bed , come with some bits , a 3 jaw chuck , 4 jaw chuck , 3 jaw soft chuck , 5MT live center , a between center bung , 4 chuck keys , tool post spanner, travel steady and fix steady. Missing a face plate

i need to adapt the chucks to the head as it had some camlock chuck arrangement on it , will be easy job and just go over the machine and a coat of paint and she's is ready for work

I have some big rollers i need to machine up , i want to make a sheet metal roller and a few other machines that i need.

and no i don't want to convert her to CNC LOL

I saved her from the metal scrap heap and i have a few jobs i need to do on her , she looks good and I will get her running right

cheers

Hi FPV,

Do you mind me asking where abouts you bought that lathe from? I'm in the market for something about that size at the moment

thanks!

KTP
08-23-2006, 01:53 AM
NC Cams you might be giving wrong information about the suitability of Rutex drives for the Fanuc red cap brushless motors. I looked for information about the Rutex 2030 brushless drive, but just see a TBA under the hookup section :confused:

Unless Rutex is doing some sort of wake and shake with the brushless motor's encoder, I don't see how you could use a red cap Fanuc motor (which has 4 output signals instead of the standard 3 hall sensors) with their drive.

I did design a version of the Pixie P100 to work with Fanuc red cap motors. It takes the 4 signals and the A, B, and index signals from the Fanuc encoder and generates evenly spaced hall signals for use by a brushless amplifier (such as your AMC, Copley, etc.). I do not have a large variety of Fanuc red cap brushless motors to test and the demand for controlling them has not been nearly as much as for regular brush and brushless motors so I have not tried to advertise the Pixie P100-F20 much (the version that works with certain Fanuc motors).

NC Cams
08-23-2006, 04:30 AM
KTP: you'll specifically note that the servo's I mention in post #104 are Fanuc DC's (IE: Model 0's and 5's). These should be suitable for driving by the appropriate Rutex servo's.

I'd also contend that FPV has sort of flip flopped between DC and AC servos that he's talked about in the multipicitious posts he's made - it is not difficult to get confused about what he's talking about at specific point in time.

One would hope that FVP has the ability to distinguish between AC and DC servos, especially when it comes to the plethora of servo's that Fanuc has supplied with the broad spectrum of CNC components and machines that they've been used with over the years, especially when he actually starts acquiring and integrating parts for his lathe retrofit.

FPV_GTp
08-23-2006, 06:12 AM
LOL = laugh out loud ;)

I think i know the difference between AC and DC

I'm trying to save money in this project and just exploring all avenues

Here in Melbourne Australia , new DC motors of 500watts up to 1 hp they asking $500+GST and i still have to buy the encoders which is between $150 to $250+GST each again and mount the bloody things

And servo motors with encoders are over a $1000 to buy new which i don't want to spend.

On ebay i see heaps of AC and DC Fanuc servos and other brands selling for second hand , i suppose its a hit and miss in the buy as if there in working order

The guys are selling them with description in working order , so i thought for around $100 to $200 USD i have the motors and encodes and some decent sized power too.

Plus shipping them out to Australia on a slow boat to china it would be worth while me buying them.

I just want to make sure there is HOBBYCNC drivers out there that can control theses motors otherwise there useless to me for the project.

And that's where i come across this website

http://www.skyko.com/products/

which has two controllers ( Pixie P100-F20 and Pixie P100 ) for fanuc motors

" Skyko Technologies is a new company specializing in motor controls.
A new product line - the Pixie P100 - is available to provide an interface between inexpensive and easy-to-use PC machine controller programs that generate step and direction signals (such as Mach3 or EMC ) and commercial motor amplifiers that require an analog control voltage. The Pixie P100 gives the user a low cost method to get professional results from their servo system. "

very reasonably priced

cheers

NC Cams
08-23-2006, 07:02 AM
Per FPV GTp,

"I think i know the difference between AC and DC"

By this time I would surely hope so....

FPV_GTp
08-23-2006, 09:58 AM
LOL NC Cams

good to see you have a GSOH , i thought you were a straight laced guy

cheers

FPV_GTp
08-23-2006, 10:19 AM
Hi FPV,

Do you mind me asking where abouts you bought that lathe from? I'm in the market for something about that size at the moment

thanks!

Hi dvsU12

bought the lathe from a private seller , thati s all he had.

where abouts are you from ??


cheers

FPV_GTp
08-23-2006, 11:04 AM
Just searching the WORLD WIDE WEB nothing on TV

come across this site mmmmmmmmmm
http://www.servo-taiwan.com.tw/?f=ServoMotor&Id=125 sent them a email lets see the price of there range of servo motors

Went on the fanuc site http://www.fanuc.co.jp/en/product/new_product/2003/0309/motoralpha3000hvis-2.html

woooooooooooooo some of the fanuc PLC controllers are sexy http://www.fanuc.co.jp/en/product/cnc/index.html

now searching to see if anyone makes servo motors in china

cheers

cheers

KTP
08-23-2006, 12:28 PM
FPV:

The site you mention (www.skyko.com) and the product (Pixie P100) are mine. Understand that the Pixie P100 still requires a motor amplifier capable of driving the servo motor you are considering. The Fanuc motors are a good deal sometimes, with the red cap motors being much cheaper on ebay than the yellow and black cap motors for some reason. I purchased a brand new in box Fanuc 5 red cap brushless motor for $200 on ebay. I searched for months for a new or almost new black or yellow cap brush motor and could find nothing under $500.

NC Cams:

Sorry, I see now that you were refering to the DC brush Fanuc servomotors. Some of these could even be controlled by a Gecko, but the Rutex would be a better match IMO because of the adjustability of the following error. Most of the Fanuc servomotors have an extremely high encoder count, and the Gecko drive only has a fixed following error of +/-128 counts. With a 10,000 count encoder, that is not much movement of the motor shaft before the motor faults out. What this means is that with a Gecko you will have to tune the amplifier fairly exactly and possibly limit your acceleration.

Or if you find a good deal on servo amplifiers you can always use a Pixie ;)

NC Cams
08-23-2006, 04:26 PM
Fanuc is NOT inordinately responsive to the onesy twosy guys who integrate. If they are/do respond,the service is NOT cheap.

Like sell your first born child and your soul to pay for any service calls.

Pixie, Skyco, Gecko, Rutex et al. are the salvation of the DIY CNC crowd. No matter what they charge, these guys will be LESS costly than Fanuc, EMI et al to the the DIY guys. My take, correct me if I'm wrong, please???!!!

If it were not for guys like Al or George or others of their ilk, the DIY CNC crowd would be like so screwed you would not believe.

FPV_GTp
08-24-2006, 01:04 AM
hi

Ok , if i can find some cheap big fanuc DC servo motors , what's the big deal in modifying the encoder section.

encoder is just a sensor like any , it has a hall affect or optical type sensor light emitting diodes and receiving diode with some sort of interrupter disc with slots in it. ( sends a SQUARE WAVEFORM either from 0 volts to 1 volts or 0 volts to 5 volts or 0 volts to 10 volts doesn't matter what the out put voltages is it can be changed to suit a particular driver.

Haven't seen inside a fanuc servo motor or encoder by fanuc that's if fanuc make there own servos and encoders or do they license out the manufacture of the servos to someone else and just brand them themselves
The biggest problem is to comprehend is one guys says stepper motors are fine another says servo motors are better .

All conflicting information

LOL NC Cams seems you are very familiar with fanucs products

I will get my hands on a unit here in Australia and pull one apart where it be a DC or AC servo motor , prefer DC as that's the path i will go down with this conversion

cheers

PS NC Cams is ee your getting accustomed to " LOL " PMSFL them me what that means NC Cams ;)

dvsU12
08-24-2006, 01:21 AM
Hi dvsU12

bought the lathe from a private seller , thati s all he had.

where abouts are you from ??


cheers

Melbourne, south eastern suburbs.
Been looking at mills too, especially the DM range of mills Standaco Machinery in Nunawading usually puts up on ebay, then converting it to NC soon after.
keep up the good work!

FPV_GTp
08-24-2006, 05:29 AM
Melbourne, south eastern suburbs.
Been looking at mills too, especially the DM range of mills Standaco Machinery in Nunawading usually puts up on ebay, then converting it to NC soon after.
keep up the good work!

hi

look in the "Melbourne Trading post " there is a guy who imports chinese an Taiwanese lathes and mills from tiny suckers to huge big machines

His got a lot of second hand machinery also , his very reasonably priced and very negotiable on price

Hang on i will get his details and say Ivan referred you to him ., sorry trading post is at home i will post it later tonight. If you have a trading post look in the back of it he advertises water damaged equipment . But lather tonight i will find his details when i get home from work


His in the Reservoir area in a Huge factory i was there a few weeks ago

what control system do you plan on using on the lathe and or mill machine to convert them in CNC mode ?
I'm in St ALbans western suburbs 15minutes out bound of the city over the westgate bridge

cheers

FPV_GTp
08-24-2006, 08:21 AM
ok

Here is the guys details Ausino Pty Ltd 129 McEwan Rd , Heidelberg West
ph : 03 9459 6011

hobby gear head lathes ... from $800 , mills from $1000 no reasonable offer refused in his ad ;)

give him a try , may pay to visit him as he has a huge factory full of machinery and accessories

cheers

NC Cams
08-24-2006, 09:41 AM
I"m pretty sure that the following link explains the stepper vs servo compromise:

http://www.cnczone.com/forums/showthread.php?t=17419

Fanuc made and bought servo motors from Gettys. Some had encoders and some had resolvers. Encoders were pretty easy to use for retrofit, resolvers not so easy.

Due to their physical size and power requirements, they are not always easy to drive with DIY servo amps. Forget Gecko - they don't have the voltage. The only thing I found suitable in voltage and current would be Rutex or AMC.

BUT, then you get into the issue of the count output of the Fanuc fitted endoders. Pretty sure mine are 2500/rev. I dunno what the drives are capable of counting at.

The Fanucs were designed to give REAL accurate F/B to a true NC controller, not merely a S/D system that looks at/for follower error. Howevr, they are retrofitted with appropriate drives and can be made to work well. You just don't get true full closed loop F/B if you merely work with follower error.

Steppers are an economical alternative to servos. However, any time you make a compromise, you have to live with the consequences there of. The following may help:

LPT Port limitations wrt driving steppers and servos, especially posts 16 thru 19
http://www.cnczone.com/forums/showthread.php?p=186255#post186255

FPV_GTp
08-27-2006, 06:05 PM
hi

ok been searching on the WorldWideWeb and it is amazing what one can find on there some resourceful information to a lot of crap . Comae across this webiste and just had to include it into this thread as im at the stage where i start buying things ; Selecting a Servomotor for an Application

http://zone.ni.com/devzone/conceptd.nsf/webmain/5D07D3F0B96B689D862568400061D678?opendocument


When you must select a servomotor for initial installation or for a replacement, you will need to consider the following data, which are shown in the table in Fig. 11-95. The first point to consider is whether the motor will be used for continuous duty or intermittent duty. The table shows the amount of continuous stall torque each motor can produce. The second rating from the table is the amount of peak torque. Both the continuous torque and the peak torque are listed in ounce-inches (oz-in.), pound-inches (Ib-in.), or inch-pound (in-lb.), and in newton-meters (N·m).


The conversion of ounce-inches, pound-inches, and newton-meters follows:

1 lb-in. = 16 oz-in.
1 lb-in. = 0.112085 N·m

The rated power for each motor is listed in horsepower (hp) and kilowatts (kW). The calculation for determining horsepower and the conversion from horsepower to watts follows.

Horsepower = (torque x speed)/16,800
Torque = oz-in.

Speed = revolutions per second

The horsepower calculation uses the torque available at the specified speed.
1 hp = 746 Watts

The rated speed is listed on the data table as rpm (revolutions per minute). The rated current is listed in A rms. The peak current and the maximum continuous AC input power are listed in A rms. The rotor inertia is rated in oz-in.2 (mass). The model numbers for each motor are listed across the top of this table.


FIGURE 11-95 Technical data table for selecting servomotors. The motors are listed across the top of the table and the data are listed down the side. (Courtesy of Parker Compumotor Division.)



Problem 11-9
Select the proper motor from the table shown in Fig. 11-95. The load for the motor is 6 hp, the rated speed is 3000 rpm, and the rated torque required for the load is at least 4500 oz-in.

Solution
Since the load requires a minimum of 6 hp and requires at least 4500 oz-in. of torque, the Z-635, ZX-635, or ZFX-635 should be the smallest motor selected. The motor could be the next larger size, but it is not advisable to select too large a motor. "


cheers

FPV_GTp
08-27-2006, 06:21 PM
Found this article also and guess what its form this forum http://www.cnczone.com/forums/printthread.php?t=6206

http://www.cnczone.com/forums/showthread.php?t=5866

a nice link , How to measure torque. http://members.shaw.ca/cncstuff/hps_part2.html

a nice wway to measure torque of a unknown stepper motor or servo motor or to apply a load on the motor to see if it is operating properly.

I will post more information in this thread as i am learning and most of the articles will be useful for me and not to mention it may help someone else.


I'm sure there is a lot of useful informtion on www.cnczone.com it is just a matter of sifting throught the information.

cheers

NC Cams
08-27-2006, 08:06 PM
FVP:

It is quite admirable the you've done that much research. However, most DIY'ers don't/won't/can't do the engineering or the math to properly size a motor. I"d further speculate that many don't do the match because they are not trained to be able to undestand the math posted in the valuable listings you posted.

They'll buy a NEMA whatever, or buy something that "looks good" off E-bay" or simply write CNCZone.com and ask "what size motor should I use for my CNC'd whatever?" and often include the comment "I'm totally ignorant in CNC/Electronics/whatever". Sort of amazing, no???

Happens regularly, happens repeatedly and probably ain't gonna change anytime soon. This is why some machines work like a charm and others hobble about or won't run properly or cut stuff accurately. Namely, improperly engineered or totally UN-engineered system.

balsaman
08-27-2006, 09:59 PM
Some use the TLAR method, and can get away with it quite well.

Eric

FPV_GTp
09-03-2006, 06:28 PM
Some use the TLAR method, and can get away with it quite well.
Eric

Hi
balsaman what is TLAR method ?? don't know what this abbreviation stands for ????

Found these Pacific Scientific 220V DC motors on the weekend
220VDC, 9.7 amp, 2.5 HP (continuous duty), 3025 RPM motors.

The shaft is 5/8 in. nominal. The length of the shaft to the motor casing is 2.075 in. There is a shoulder just before the motor casing.

From the end of the shaft to the shoulder is 1.93 in.

The motor casing is 11 inches long and has a diameter of 4.5 inches.

Here a few pictures of the motors pity there not around .750 to 1000watt power output.

Looking at theses motors there similar to the ones the guy converted in my thread that i posted in here some where.

have to say there a beautiful motor.

cheers

Kipper
09-03-2006, 06:45 PM
Try Acronym explanations (http://www.acronymfinder.com) It helps me no end mate!

Al_The_Man
09-03-2006, 08:03 PM
.

Here a few pictures of the motors pity there not around .750 to 1000watt power output.

have to say there a beautiful motor.


Before you get too elated, I would keep in mind that many manufacturers cater to the Treadmill motor manufacturers and I have found that many motors are not quite up to servo grade, A couple of give aways, the HP rating given for the size of the motor, the armature winding, amount of poles etc, (you can just see a sample through the endbell.
The lack of rear shaft for encoder, tach etc.
If they only have two brushes.
If you look through the brush holder to inspect the commutator, you might see very few comm. bars, indicating few poles.
I bought some Baldor 'Servo' motors about this size, they turned out to be treadmill quality.
You could use them for spindle motors though.
Something to keep in mind when shopping for DC servo's.
Al.

FPV_GTp
09-03-2006, 11:37 PM
hi

MMMMMMMMMMMM " TLAF = The Little App Factory "

" TLAF = Two-Line Atomic Fluorescence (laser diagnostic tool for flame temperature measurement) "

MMMMMMMMMMMMMMMMMMMMMMMMM would like to get balsaman's version of TLAF , LOL

hello Al_The_Man , yes you are right on some of these DC motors there treadmill or vacuum cleaner motors even the AMETEK PERMANENT MAGNET DC MOTOR , cheap and nasty.

But Pacific Scientific 220V DC motors seem like a good unit and i visited there website www.pacsci.com , the have there low grade everyday run of the mill DC motors right upto there high quality servo and stepper motors and controllers , yes once again very expensive.

Thats why i would like to get hold of a commercial servo motor that is knacked to pull it apart and have a inspection of one inside to see how it is constructed.

cheers

balsaman
09-05-2006, 12:55 PM
TLAR = That Looks About Right

E

FPV_GTp
09-07-2006, 05:57 PM
hi

just a few intresting websites of suppliers - will post as i find them in here for others to veiw also


surplus supplier -

http://www.eolsurplus.com/StepperAndServoMotors.html#LEADSCREWS



MOTOR CONTROLLERS , only small units as far as amprage is concerned -

http://www.makingthings.com/products/documentation/teleo_motor_controller_2x2a_user_guide/

http://www.standa.lt/products/catalog/motorised_positioners?item=191



TABLE OF DC MOTOR SPECIFICATIONS -

http://www.tokushudenso.co.jp/E-motor.htm


those pacific science DC motors will cost a futune to ship 9 motors to Australai , was quoted over $1100 USD just for freight :(

still searching for motors ??????


cheers

Adobe Machine
09-08-2006, 12:49 AM
I'm just courious, can a US Citizen ship a package to an Australian resident with out a lot of B.S., or have our great civil servents and POLITICALS screwed that one up too ( both sides ). Used to ship packages to an AUS. solider I met in S.E. Asia with no problems , as certain items made in USA(legal stuff everyone) were a little "difficult" to get in Aus. at a decent price.... just courious.

Adobe (old as dirt )

FPV_GTp
09-08-2006, 07:41 AM
hi

more commercial manufacturers of cnc building components


AC Servo Motors
ABB
AEG
Allen Bradley
Baldor
Baumuller
Bosch
BBC
Bridgeport
CEM
Cincinnati Milacron
ElectroCraft
Emerson
Eurodrive
Fanuc
Fugi
Futaba
Getty's
General Electric
Giddings and Lewis
Goulds
Hitachi
Indramat
Kollmorgen
Matsu****a
Moog
Pacific Scientific
Panasonic
SEM
Sinano
Siemens
Tamagawa
Toshiba
Yaskawa


DC Servo Motors
ABB
AEG
Allen Bradley
Baldor
Baumuller
Bosch
BBC
Bridgeport
Cincinnati Milacron
Cleveland Motor
ElectroCraft
Fanuc
Getty's
General Electric
Giddings and Lewis
Glentek
Goulds
Indramat
Inland
Kollmorgen
Mitsubishi
Matsu****a
Pacific Scientific
Panasonic
Peerless
Peerless-Winsmith
Porter_Peerless
Powertron
Reliance
SEM
Sinano
Siemens
Tamagawa
Toshiba
Yaskawa


Spindle Motors
Allen Bradley
Baldor
Cincinnati Milacron
Fanuc
Getty's
Indramat
Komo
Mitsubishi
Siemens
Yaskawa

Stepper Motors
Air Pax
Allegro
EAD

Encoder/
Feedback Motors
Absolute Encoder
Allen Bradley
Alpha Encoder
Baldor
Beta Serial
BBC
BEI
Bosch
Fanuc
Fasco
Fugi
Hall Sensors
Harowe
Heidenhain
Hitachi
Incremental Encoder
Micron
Mitsubishi
Renco
Resolvers
Sanyo
Sanyo-Denki
Siemens
Sinano
Sony
Tamagawa
Toshiba
Yaskawa
Nanotec
Pittman
Tandom
US Digital
Vexta
Yaskawa

BobWarfield
09-08-2006, 11:50 AM
FPV, I understand it's expensive to ship from the US to Aus. What about from places like Malaysia?

A lot of surplus linear motion stuff including linear guides, ballscrews, and motors, is coming out of Asia as they close obsolete chip fabs and retool them. A number of eBay sellers of these items are actually located in Malaysia, Singapore, or similar places. Perhaps you can find one and solve your shipping problem.

BTW, TLAR is much too subjective for critical applications like this. I much prefer SWAG for precision engineering.

I wouldn't sweat the TLAR approach too much NC. From what you've said, getting your cam machine to work to satisfaction involved a lot more trial and error than math and engineering ("We finally discovered the gain was turned off for one of the axes"). The TLAR crowd just iterates from a slightly less optimal starting point.

My favorite TLAR approach is a method of blackjack card counting that I have perfected. I used to count in Vegas the traditional way, but frankly it is boring, and it involves too much work to be fun, though you will win. My TLAR alternative works just as well, but in more limited circumstances, namely, it works only on cruise ships. I will now divulge the secret (drumroll please!):

1. Every cruise I was ever on holds two blackjack tournaments. One at the beginning and one at the end off the cruise. Do not enter as a contestant, but go to the first tournament as a spectator.

2. See who wins 1st, 2nd, and 3rd place. They will announce it. Those people are all card counters with a very high certainty. Memorize their faces!

3. Whenever you want to gamble, just cruise into the ship's casino. At least one of the 3 winners will be there. Sit at his or her table. Doesn't matter where. Always bet exactly what the counter bets. Their bet will increase if their counters says the deck favors the players, and it will decrease if the deck favors the house.

You can thereby "count cards" with no mathematical ability whatsoever and do quite well. That's not so different than getting on CNCZone and letting some other fellow figure out your motor size for you!

Cheers!

BW

NC Cams
09-08-2006, 05:35 PM
The "trial and error" you alludedto involved figuring out what what other people had "engineered" and then fixing that stuff with truly re-engineered hardware in return.

Although we did some bearing shimming to affect preload, We had at least an IDEA of what we were doing and at least knew how to qualify what we were doing - not just slam something together and hope for the best as some follks have a want to do.

For example: when we wanted to preload the ball screws, we at least knew how much preload we could tolerate in the nut with o/s balls before we'd brinnell the balls or raceways. Far cry from "I dunno, just preload the darn thing" doesn't work.

We also at least knew what bearing stiffness was and how and where to look for backlash in the system. Some folks figure that "backlash comp" will magically deal with it (it DOESN'T) and that's what makes the difference between making something work and living with something that doesn't worki predictably.

I read somewhere where someone installed 2-3 sets of ball screw bearings and STILL had slop. Don't see how that's possible if you had the bearings peloaded properly, knew how to check them for proper assembly and knew how to find where else the backlash could be instead of installing 2-3 sets of surely expensive bearings. Parts swapping is NOT re-engineering something to make it work correctly.

My biggest beef is with folks who mess with electronics and admittedly say "I'm illiterate with respect to computers or electronics". I simply do NOT see how someone can hunt and peck thru the diagnostics of electronic systems and/or computer systems and not even know Ohm's law. But they do and somehow proove that blind squirrels do find the acorns evey so often.

Sometimes you can take advnatage of card counters. But in some cases, when you're in the shop late some night and the things crash and there's nobody to call, having the ability to craft up a sollution WITHOUT having to cribb of of someone else does have its advantages. When it is only you and the dealer at the table, it is you versus him (the house) and them's lousy odds.

If you're going to play with technical stuff, you really should learn the math and science involved with it. Life isn't always made up of plug and play software and you do have to do some math every so often....

fkaCarel
09-08-2006, 06:14 PM
BTW, TLAR is much too subjective for critical applications like this. I much prefer SWAG for precision engineering.

Sad, sad, sad, very sad. There are people on this world who are doing their utmost to do it right and be responsible. You are propagating louth-mouth engineering. Your approach is just an insult. If you design bridges, please mark them as "designed by BobWarfield", so I can avoid them.

BobWarfield
09-08-2006, 06:15 PM
Golly NC, I hear you, but come on, it's a hobby. Why have a beef with people at all? You're not paid or required to respond to them. Their failure is not your failure. Your knowledge of that stuff let's you be the expert, which you seem to enjoy doing. They already see you have that knowledge and respect you for it without needing to be derided as well. The pennance of the non-experts is the inevitable pain they have to go through, so again, why be annoyed at them?

Plug and play actually works very often, even most of the time for hobbies. These guys aren't making NASCAR cams. Heck, most aren't even making brass candlesticks for their wife. There is a lot of amazement in seeing a CNC router constructed of particle board (anyone remember, "I am attempting to construct a mnemonic device out of stone knives and bear skins"?) actually do anything at all. The thing is made out of saw dust and Chinese scrap motors for cripe's sake!

I have an engineering degree from one of the "good" schools. The difference between my computer science degree and an electrical engineering degree from the same school was one chemistry course (go figure!). I know Ohm's law and a lot of other nifty math. Guess what, that isn't the real important thing a great engineer has going for him. The great engineer has a logical and intuitive mind. He sees patterns. He extrapolates well. He can take two unrelated solutions and see the common link needed to tie them together and make a third solution to another completely unrelated solution. He can get beyond the conventional wisdom and do something new, in other words.

I run Engineering departments for software companies, large and small. I can hire guys all day long that have those great engineering degrees from "good" schools. They can tell me the equivalent of Ohm's law. The real question is, "Are they effective problem solvers?" Turns out for computer software, being from the "good" school and knowing the math is not such a good indicator. I know good school guys that are disasters and no school guys that are some of the world's finest programmers. Length of time on job is also not a good indicator. Having succeeded in building a meaningful part of software equivalent to what you are trying to build is a good indicator, but that didn't "make" the guy good, it only proved he was good. You either have it or you don't. Most, but not all, of those guys also have tremendous humility. I really respect them all the more for that.

What looks like plug and play may just be that good problem solver knowing he has a problem similar enough that it isn't worth re-engineering. "Trial and error" for that good problem solver is tying those disimilar solutions together in a rational way that works. The path may be obvious (deductive logic) or uncanny (intuition). Both work, and we can't seem to explain it very well or teach people how to do it. You either can or you can't.

So hey, let's not kid ourselves we're gonna take out Haas with our MDF machines here, or even with our fancy re-engineered Bridgeports (the Haas still does it in less time, no?). Let's just have some fun and not run the other guy down. Everybody has something to contribute, we're all a lot closer to one another than we'd like to admit, and yes, trial and error is trial and error, perhaps with a slightly more optimal starting point as I said.

BTW, I rather liked the discussion from the guy who tried the 3 sets of bearings.

That guy (Vince was his name) had a lot to contribute, did a good job on his Bridgeport conversion, and multiple sets of the experts let him down when he paid them to come out and work their magic. They just recommended yet another set of bearings. You should read his thread all the way through if you don't think so, because I thought you were unfair to him. What he did sounded no different to me than what you did as far as hiring experts and following their advice.

If you read the thread, Vince had actually looked at all of the sources of backlash you mentioned and had experts confirm them to no avail. He was pretty darned systematic in engineering his conversion and in trying to diagnose the backlash. The experts either said it wasn't a problem (ballscrews, but those experts had a vested interest having sold those screws), changed the bearings but it still didn't help, or ground and hand scraped ways and gibs, and it didn't help.

I guess he could redo all of that again, which you seem to suggest in your note to him, but he did hire the experts and how does he know it'll come off any better the next time around. Vince is right where I'd be in his shoes. He wants to hear something new to check. Something the experts haven't thought of. A different way of looking at the problem because the conventional wisdom and the experts haven't been able to get it yet. That's usually a good sign in my experience.

BTW, I assume N4NV is his ham radio call sign. It's been a long time since I was a ham, but you used to have to know Ohm's law to be one of those too.

Best,

BW

Kipper
09-08-2006, 06:20 PM
SOooo FPV are you winning yet? :D

FPV_GTp
09-08-2006, 06:49 PM
hi

LOL Kipper , Im just doing my studies , eventually i will have a PHD in electronics a masters in Mechanical engineering and god knows what else.

Ok guys i'm a big boy , don't need a hand to be held , just quizzing and asking questions here.

BRB , goggle search , will find out what ohms law is LOL , think i encounter Mr Ohm's back in grade 3 LOL

PUTTING DOWN someone is not my style nor do i have to take someone's advice.

Yeah would be great if i had a spare $300,000 dollars to purchase a commercially made machines , but its not the case.

Guys lets take the softer approach and discuss in this thread be nice to one another
(((((((((((((((((( GROUP HUG )))))))))))))))) LOL

I don't have any government grants to fund my projects at hand ahead of me , and R&D trial and error mmmmmmmmm i would have to think 99% of projects are done this way in the world. Level of expertise thats another story in its own.

Guys im not trying to re-invent the wheel here , seen some great DESKTOP cnc machine lathes , mills , plasma tables and alot of other differant machine fellas have made and im not be sexist here :)LOL . I'm just doing a FLOORTOP cnc machine .

Once again guys be nice to one another PLEASE ;)

cheers


PS - abbreviation LOL = Laugh Out Loud

Adobe Machine
09-08-2006, 11:10 PM
Thanks for explaining "LOL"..I was afraid to ask my 2 daughters who live in the area ( both are very good w/computors, in fact one is a Phd.math) what LOL and some of the other abbreviations stood for as they have giggled at me before over some of my KLUTZ approches to the computor,anyway I have a question for N.C. Cams:
Over the years in order to stay in business and keep a medium size shop operating , it has been necessary to repair--reload ball screws, if in fact I could determine that was the cause. ( as you have attested to, in fact a lot of the problems are in the "fixed" bearings, not the ball screws )
I have gotten pretty decent at it, but you stated that you were able to figure out BEFORE re-loading how much of an oversize ball to use. I have tried using trig , even had a math prof and programmer help me try to develop a program to assist in determining max. oversize and /or stagger, to no avail...in fact, I finally made a nice wooden box with dividers and my wife lined it with soft felt.Bought a large assortment of chrome 52100 oversize in the common base sizes which we also bought...I have ,because of experiance,learned where to start with oversize, but it is still trial and error to a certain extent, more art than exact science.I just wondered how you figured oversize PRIOR to stuffing ? Since the effect of oversize is accumulative through the length of the effective spiral ( not the areas above the return tubes) and effects four areas of contact in partial sphears, that no matter how well ground or rolled are the same throughout, we could really never compute the oversize.

I'm real glad the engineers figured out an effective method with double ball nuts and their hardware that effectivly eliminates most normal backlash at the ball screw /ball nut, and still has reduced rolling resistance.

Adobe (old as dirt )

NC Cams
09-09-2006, 11:37 AM
RE: Engineering of o/size balls. This depends on if you are an OEM and are MAKING screws or are a user and trying to REFIT the nuts with O/S balls.

The OEM's order custom sized balls - However, when you service,them, you're stuck with buying what you can get your hands on - BIG difference.

When they make bearings or ball screws, they 100% measure the inner and outer race thickness/raceways and then calculate the ball size they need to obtain the desired clearance.

At one time, they used as many as 15 different ball sizes in either 1 or 2 micron steps to make bearings. The way they kept the balls separated and yet properly synchronized to the proper rings is a trade secret but they could do it at hour after hour, shift after shift and bearing after bearing. With better size control of the raceway grinding, they dropped this down to 10 ball sizes but they STILL 100% select fit the balls to establish the proper bearing clearance.

The company I worked for made their own balls so they could make whatever size they wanted/needed. THey made their balls for both the bearings and the ball screw/nuts at the same plants. The "calculation" was a very sophisicated algorythm (sic) that dialed in the right ball selection from the measured raceway info.

Re: service fitting of balls = this is a bit more of a developed/iterative art than a true calculated science. In this case, you're better off finding a shoppe that does LOTS of screw rebuilding and rework.

Why? Because, good shops will go to the trouble of at least buying balls in selective sizes so as to refit screws with reasonabley proper preload.

When I did my screw tune up, I called several shoppes and 'interviewed' them over the phone. I told them what I wanted and quizzed them on what their capabilities were.

When I found a shoppe that measured ALL the balls, and stocked balls in 0.0001" size increments IN STOCK and also measured/certified each screw for break away and rotating torque once they refit them, I concluded that this shop was one that knew what was going on "inside" the screw/nut. So I sent them there and to no surprise I got EXACTLY what I wanted.

Sometimes, you can calculate what to do and do it. Other times, you merely need to know how to do stuff properly. At that point, you can ask around and FIND a subcontractor to do what you want done with at least a reasonable possibility for success...

Re: Vince's "experts" who consulted him on the backlash. I'd hardly consider these guys "experts" if they couldn't find out the source of the backlash. It doesn't take a PHD in mechanical engineering to understand what backlash is - essentially it is cumulative slop. Even though I'd gone thru my machine, the service guy I called in went thru each and every check of what I did (re: screws, gibbs etc) to see if there was something I missed. Heck, I even showed him a thing or two, especially when it came to the bearing preload side of things. The results of that escaped have already been documented.

EDIT: BTW, I did NOT hire experts to fix my mechanicals. That part of the troubleshooting, diagnostics and repairs were all done by moi. The "expert" was called in to tune the servo's and address some computer gremlins that I didn't have a clue about. I'd be real wary of ANY expert who walks in and points to any "magic bullet" fix for any piece of equipment. I've learned that life just isn't that easy to solve problems that way.
END EDIT

In mills, static backlash it is TYPICALLY found in ball screws/nuts, gibbs, ways and/or ball screw support bearings. If these are RIGID, and the software isn't overcompensating, slop/backlash can be FOUND, QUANTIFIED and ELIMINATED.

Heck, we found the root cause of ours by simpy mounting a dial indicator in the spindle and having a 270 lb monster friend leaning on the table in 4 directions and watching if the table deflected (no kidding). Then again, we're engineers and not CNC machine repairmen and we didn't know a better way.

We did the "pot roast" lean to find table back lash and gib slop/wiggle as well. Once we located the source and magnitude of the deflection (and there were MULTIPLE SOURCES), we addressed the root causes of same one by one. NOTE: there was NO magic bullet. It took a while but we got it pretty darn good - better than most Bridgeports anyway.

Point is this: we had 1 known set of good, properly preloaded bearings for each screw. If you install 3 sets of "good" bearings and you still haven't eliminated the backlash, I'd contend that the true root cause of the backlash was either overlooked or misdiagnosed.

BTW: if the 3 sets of bearings Vince nstalled in the mill were aftermarket dupes of OEM bearings, I'd contend that they weren't EXACT factory equivalents with respect to preload method and amount. I know how some "aftermarket" bearings are 'engineered' and, trust me, it isn't always done properly!!!!

Adobe Machine
09-09-2006, 12:46 PM
So my point is this: Re-loading to eliminate backlash in a ball screw at the hobby leval, or small shop leval is not impossible, but it takes:
1) A clean,uninterupted enviroment

2) A steady hand, most important PATIENCE. ThaT means the ability to load and possibly unload the same ball nut several times for " FIT ", and not get mad or discourged.

3) tools, most hobbiest have or can make
(a) a set of quality tweezers. I gently heated mine and formed cups on the working end.
(b) A pusher. I have several sizes of dowels, use the one just slightly bigger than the balls
(c) A micrometer and the ability to measure tenths.

4) I chuck the ball screw on one of the lathes as it is easier for me to clean and inspect the race ways. I use some large string, put the lathe in "slow" and use the string to clean deep in the raceways. This is where I load the balls as you need to be able to concentrate on the loading, not the ball screw slipping off a table.
The important thing is selection:Just because you have .004 in backlash, does not mean you start at .002...no, you start a tenths oversize...if we had
.004 backlash on a 1.125 shaft with .125 balls, I would start at .0003 over size.If you feel any binding, back off,dump the loaded before damaging the nut or screw.. keep everything clean and oiled as you go along..you are going to use vasoline or equiv.for the return tubes. ( inspect the ends of the return tubes , make sure there is no crushing or slivers of metal on the ends)

I would have to say that for the leval of hobbiests and small shop people that I have seen here here in the CNC forums they could ,if necessary,re-load to eliminate back lash if that is the true source.. it is somewhat of an art, not rocket science ( read skill,patientce, determination.)

With the advent of double ball nuts and adjusting hardware, this is the easy way out if there is room and you have the $$$, but if retrofitting some of the older machines, it makes economic sense to reload your own,if there is no damage to the nuts or screws. The cost of sending a set of screw and nuts to a good ball screw shop for regrind, reload ect could bring the wrath of wife down your neck...remember this is a hobby for a lot of us.

Adobe (old as dirt )

NC Cams
09-09-2006, 03:27 PM
Adobe: you forgot one VERY important part = presource some oversized balls and get several sizes - you'll inevitably need some size you don't have if you simply buy one size and assume that it will work.

Try Winstead Precision Ball - at one time had balls in size ranges of 0.0001" or so. Last time we bought any you had to buy something like several hundred as a minimum. If you REALLY want smooth running, buy grade 3 balls instead of grade 10's 25's or 100's. Unbelieveable difference!!!!

NOTE: some ball screws INTENTIONALLY do NOT use the same size balls. Sometimes, they go small/large (ala oOoOoOo ) so as to facilitate ball rotation - the small balls act as "idler rolles" for the big ones. Why? The small ones will tend to try to rotate in the OPPOSITE direction of the big ones.

Therefore, don't just dump the stuff out and start throwing something bigger at it. Measure what you have to see what you need to start with buying. Sadly, like a lot of stuff you have to engineer to make work, there is NO INSTANT GRATIFICATION METHOD AVAILABLE FOR THIS FIX.

I'd be more inclined to use very light spindle oil to assemble. This offers less drag and will enable you to determine drag torque more readily once you load them completely. Once you're assembled you can grease them - Shell Alvania #2 is an acceptable grease.

Max tolerable preload is hard to quantify. WE chose a "mechanical/draggish" feel for ours. You can literally "feel" the balls roll into and ouf of the load zone. The drag is noticeably higher but not intolerable. But if you move the DRO 0.0005" the table moves likewise. Small price to pay for what we do.

CLEANLINESS CAN NOT BE OVEREMPHASIZED. Put it this way, if your hands get dirty (as opposed to just oily) while doing it, you don't have stuff clean enough!!!!.

BTW: just to have our ball screws reloaded, I think we paid something like $50 each. Condsidering the aggravation, it wasn't worth the effort for us to do it. I don't know what a regrind and reload would run...

Oh yes, and don't forget to check fit in several places - if the screw is unevely worn, you'll have to either live with clearance (oh well) or binding (not good) in one place or another....

Or there is the TLAR method - throw whatever the heck you can find at it and then complain that it still doesn' work right (too tight or too loose) because the parts you got were garbage.

Adobe Machine
09-09-2006, 05:18 PM
NC Cams. I refer you to Salem Speciality Ball Co ( www.salemball.com) click inventory,click chrome steel, click inches..excellent selection, no minimum, fair prices, most are in fact grade 25, chrome steel, 52100 alloy, which is more than sufficient for a home hobby shop or a small shop.Grade 10? Doubt if many of the low to medium priced CNC machine tools use a grade 10, and especially when a person is doing a re-load on a used ball screw !

$50.00 for a reload ( and from your prior post, checked the breakout torque and running torque, which takes a nice piece of equipment to test those values) is a super bargin.. When I was in business could not even find a place to do that,unfortunatley, had to package them up and ship them out for re load, damn ,the freight back then was more than $100.00 both ways, plus we were always needing the machine back in order...I would say that that price is exceptional, or that type of business is really slow in your area...I can not even get a plumber here for less than $ 65.00/hr..
We have to be careful of too much preload ( drag ) in Arizona if we are not working in a climate controlled shop..With out side temps reaching 115 plus at times, the machine heats up faster and gets hotter, stays that way longer.Had a friend and competetor buy a set of pre loaded "0" back lash ball screws from a known good supplier back east, by the afternoon of the 1st day of use with the servos off, they could barley turn by hand.The next morning they were fine.They were replaced three times under warrenty, had one of their contract service guys come and install one of the sets, same story...they had to decrease preload , after that they worked fine. I judge preload by gripping the shaft with both hands and arching the shaft,if the ball screw will not freely swing, but I can turn smoothly by turning the ball nut by hand, it is good to go, and all else being correct, will have tenths in backlash.
(25 year old Tree Mill)BUT I'm not making high $$$ cam profiles for the camgrinder either. I Make nice billit pieces for my hot rod and have fun, even in a wheel chair ! ( and for my lathe retrofit )
If this were for production, and my living depended on holding tenths day after day , would not be retrofitting a 25 year old mill and a 50 year old lathe...or building a mini mill from HF...But even if it is a hobby, I still strive for accuracy at an economical price, as I see most of the people who subscribe to this forumn are doing. I'm just real impressed by some of the nice machinery being built/retrofitted by people who just enjoy this as a hobby who use the "Zone" for questions and answers, and the people who are experts taking their time to answer questions with out any pay or other rewards.

Adobe (old as dirt )

NC Cams
09-09-2006, 07:54 PM
People seem to miss the purpose of my posts.

There are all kinds of ways to get by with this that or the other procedures - be it sage wisdom or SWAG's that become rules of law due to folk lore.

However, it is not often that true machine tool procedures and/or bearing engineering methods are provided for folks to follow - ascribe to.

When I started on my mill "upgrade", the mere intent was to eliminate the backlash that was causing flats to be milled at the direction changes. These were happening while a friend was using the mill to machine golf club heads. We did NOT start out to cut cam profiles but golf club heads!!!!

Since the guy who was using the mill and I were were both bearing engineers at the same time for the same bearing company earlier in our careers, we pooled our knowledge to solve the problem that was messing with the aesthetics of his billet putters. Only we got sort of got carried away....

First we tried to find the source of the backlash. He was the "pot roast" who leaned against the table. Well, when you have near new OEM ball screw bearings in the system and can see 0.004" backlash simply by leaning on the table in X and Y directions, it doesn't take a PHD in mech engr to see/find/figure out where the slop is.

Since he had worked with bearing shimming to solve front end wandering with FWD bearings, we used his experience to see what, if any affect, increasing the preload of stock bearings would do.

It was a Sunday afternoon and the only shim stock we had was aluminum foil so we cut shims and started playing. Crude but effective. Result: the more we preloaded, the less slop we had (eventually none) BUT rotating torque of the screw shaft became unbearable.

Sollution: use true ball screw bearings. Why? They have much higher contact angle, much higher rigidity and much much less deflection even with nearly 500lbs of preload. Even with this monster preload, the screws turn with the same or a bit less torque than our shimmed OEM bearings. Long story - too technical (high load and high pressure angle yields low rotating torque under rolling friction) - just trust me, they do.

Fortunately, we had friends and got some surplus ball screw bearing cores from the manufacturer - no different than buying from E-bay except we got EXACTLY what we wanted instead of pot luck SWAG stuff folks buy on price at EBAY. We also know how and where to get them preloaded PROPERLY to what we wanted/calculated for our needs (that's where the engineering part came in real handy).

However, there was STILL some slop. This led to preloading the ball screw escapade. One of the questions that the guy asked was the speed at which we'd be running the screw. For reasons cited in Adobe's post, you DO have to consider speed.

Reason: more preload creates more frictional heat especially under high speed jog modes. Y'all alreadly have heard about the results of the screw backlash results from Adobe. BTW, we knew that too from our work with wheel bearings and machine tool bearing work - another part where engineering experience came in handy.

Here's where things got REAL interesting. Even with the preloaded screws and the monster preloaded trick ball screw bearings, we still had backlash and non- linearity of motion at direction changes.

THis was NOT easy to find/fix until you start to mess with gibb adjustment. Sollution: simply tighten them up.

WRONG!!!!

Do that and the damn table sticks at direction changes and you end up with the table 'popping' once you get enough force to overcome the gibb friction at direction changes. Patience and experimentation (IE: make change, record data, analayze, repeat until you get desired results). NO magic bullet fixes here, guys.

Once we figured out the gibb adjustment (it is NOT documented anywhere in the BPT service manual - in fact the service guy asked me how the heck I got it that linear/positive), you saw unbelieveable repeatablity at direaction changes under both manual and servo control.

The point is this: if you know all the trick stuff to do, you can take whatever shortcuts you want/need to for your particular situation. It all depends on the accuracy level that you want to achieve.

But if you don't have a clue and you don't know how stuff works, you can throw money at the machine until you're blue in the face and you'll only make other people wealthy.

Did I try to achieve master level accuracy at the outset??? Hell no. We were simply trying to mill golf club putter heads without flats at the direction changes. Once we got the thing 'golf club grade', the guy said, "bet you can't mill a master with it" - a challenge to which I simply could not slink away from.

Even the BPT specs said the accuracies of a brand new machine couldn't get to the levels we did. Since the factory doesn't "blueprint" machines like we did, they can't. But we did simply because we thought we could and we ultimately proved ourselves right.

However, it was only after we eliminated the 'cheap' OEM bearings and 'barely adequate' adjustments that they did to make the mill saleable, did we find that you could literally mill circles that were UNBELIEVEABLE round and irregular profile shapes with uncanny accuracy.

That's when we tried to mill the masters and the epiphany was complete. The law of unintended consequenses, pure and simple....

Would/should eveyone try this? I don't know.

It takes time and money and the ability to withstand a lot of "you're crazy, that won't works" from all kinds of people who "know better".

But when the thing works to an unbelieveable level of performance, the doubters still walk away in disbelief after they even see it work for themselves.

I don't recall in ANY of my posts saying that "my way is the only way to do this that or any other thing".

It is definitely a "top shelf" way.

It is a way that has been proven.

It is a way that should provide exemplary results if followed completely.

And I dare say, it provides more insiight into what's REALLY going on than several 'experts' who waltz in and suggest changing the same bearing 2-3 times and still can 't exlplain why a ball screw has too much slop.

I never meant do diss Vince - I merely feel that he was a victim of some shyster experts, no more, no less.

Maybe the reason why folks take exception to my methods as outlined in my suggestions/postings is that I don't charge enough for my "expertise"???

Maybe I don't but at least my stuff works and it doesn't have backlash. Moreover, I've outlined for all to see/follow/understand how and why I did what I did to eliminate it.

BTW, I've also outlined a number of alternate bearing P/N's that are much less costly than the high $$$ ball screw bearings that I used to fit in my machine. Sadly, ANY time you talk angular contact bearings, you're talking $$$.

Speed and accuracy cost money - how fast and how accurate do you want to go/be????

Adobe Machine
09-09-2006, 08:27 PM
NC Cams: I have said it before and will again...your knowledge has helped every one who retrofits/builds , repairs machine tools who subscribe to this forumn..beyond a doubt you have dedicated your self to learning your craft, and no doubts you are ( were) not just the regular joe bearing engineer, but really above the norm and helped a lot of people. Mr. Bob Warfield is one of those persons also,having helped thousands of machinests and corporations with their software and machining problems.What we and others are saying is, in most instances this is just a hobby, and the $ $ $ are just not there to purchase real expensive bearing sets..so we must do the best we can with the $ $ $ avaliable and appreciate your advice on the lower cost ones...and your opinion as to what we could expect in reduced back lash, better performance, etc., along with your expertise in diagnostics determining where the back lash is comming from...this is invaluable to every one, but show us flatlanders a little patientce...know what I mean ? I had a brilliant commander in South East Asia give the cadre (non coms and above ) some real good advice: Coax them flatlanders, don't yell, don't scream, or them ole boys might turn their long rifles on you.. I have tried to take that advice all my life.

Adobe (old as dirt )

NC Cams
09-10-2006, 10:54 AM
I've learned via a number of race teams and former employers and employees that I"ve worked with over the years that one's students/employees will rise to the level of the expectations that one sets out for them. Expect crap, you won't be disappointed - expect jewelry and the students will strive to create it. Some do it out of fear - some out of respect (Frankly, I"ll take either as fear can be turned into respect once trust is established that you know what you're talking about).

To get someone to rise to a higher level of performance expectation THAN EVEN THEY FEEL THEY CAN ACHIEVE is a wonderful thing. How do you instill that feeling via postings a message board??? Explain 14 times how to build the same power supply or a simple "go here and do it THIS way" link? I'd contend that eventually, there are only so many ways to build the same 36 volt P/S with 3 PC power supplies. The unfortunate thing about the written word is that tonal inflections are not conveyed. What a person voices TIC in writing can be taken literally by others.

One of the best instructors I ever had was the meanest SOB who ever taught Algebra. The SOB deducted 3 points on a test because I was "messy" in correcting a proof - the damn 3 points took me from a C to a D in the class for which I caught holy hell for. Needless to say, I never did that again and his "logic" served me well, however, thru countless engineering exams/problem solving exercises later on in lift. That was 38 years ago and some of his lessons still ring home today.

Point is, life's lessons are NOT often pleasant to learn. My bedside manner has both served me well and has been my curse. Some folks like the "frankness/no bull" approach I take and others find it too terse, perhaps offensive. Sadly and fortunately and unfortunately, I learned from task masters BEFORE P/C was deemed necessary and proper and I survived the experience. Hopefully, the members can absorb the positive and deal with the rest.....

If I or anyone else provides the "here's how you do it" approach, and it involves high end parts, the reader has a choice - use it or not. They can also ask for alternate methods that could be done to achieve comparable results for which I"ve supplied viable alternatives if at all possible.

There are many paths to the same water hole. Some are direct and others are more circuitous. Other paths will take you anyplace BUT which some people tend to follow due to a lack of experience or education regarding the technically proper way to do things.

Yes this is a hobby. But it is a TECHNICAL one that involves the use of engineering principles. If you're goint to get invovled with such a technical hobby, shouldn't it at least be wise to become familiar with the 'disciplines' associated therewith??? Unfortunately, discipline is not always fun to learn nor nice nor is it always politically correct.

Most instructors of engineering disciplines do NOT try to become "friends" with their students. They are there to instill knowledge. As a student, you can either absorb it or not - pass or fail - your choice. Yes this is not college but the choices are still the same.

I'll try to do a better job of recognizing that this is a "hobby" but it surely isn't a non-technical one and it DEFININITELY NOT an inexpesive one. Some issues can be solved on the cheap - others are not so easy to do without spending time or money to fix or to learn how to do with reason, proper logic and some study into the proper technical discipline(s).

FPV_GTp
09-11-2006, 05:07 AM
LOL NC cad

I do have late model PC's and laptops , Im not that much of a tight ass LOL

cheers

FPV_GTp
09-11-2006, 06:21 PM
Hi

Ok, after some serious considerations , gecko drivers http://www.geckodrive.com/ is going to be the electronics behind my FLOORTOPCNC lathe prodject.

cheers

Adobe Machine
09-11-2006, 10:19 PM
cool ,have you got the mechanics organized yet ? In so far as ball screws or using the present system and driving them with a servo ? Have you picked out software yet ? Sorry, if these questions have been answered, but sifting thru the thread it got a little confusing to say the least !

Adobe (old as dirt )

balsaman
09-12-2006, 12:36 PM
Hi

Ok, after some serious considerations , gecko drivers http://www.geckodrive.com/ is going to be the electronics behind my FLOORTOPCNC lathe prodject.

cheers

Make sure you use motors that are rated at around or less than 70 volts (I am assuming you are going gecko 320's) Higher violtage motors will work but you will not get rated speed. If you are going steppers, disregard the above.

Eric

FPV_GTp
09-20-2006, 03:04 AM
Hi

Just amazing how the net has changed ones way of shopping in a arm chair with a drink in the hand ;)

found this on ebay , i will take a guess and say this person is possibly a cnczone.com member

Ok it is www.homeshopcnc.com Granada Hills CA, United States

this is You are bidding on (2) 1200 oz/in and (1) 1780 oz/in square frame stepper motors (4-wire), (3) G201 microstepping drivers from Geckodrive Inc plus the components needed to build a 68V , 11.7A power supply.

These components are most of what you need to retrofit a Bridgeport type Knee Mill to CNC. All components are new and never used and are well matched in their electrical ratings to make an excellent CNC controller. This has been proven on numerous knee mills.

We recommend Mach2 software and breakout boards available from either pmdx or cnc4pc.

The 1200s will drive the table on a 1:1 ratio ; the 1780 will drive the knee on 2:1 or 3:1 ratio with excellent result.

If your application requires a different motor combination please email us.

See my other items for more CNC components.

CA residents pay Tax. price: US $799.00


http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=160031571055&ssPageName=ADME:B:FSEL:US:1


Servo Motor 850oz/in Peak Torque CNC Router Mill New price: US $199.00

850 oz/in Peak Torque 72VDC Servo Motor: Nema 34

Skewed rotor design -This is an actual servo motor, not just a DC motor with an encoder on it. The marked difference is in the skewing of the rotor resulting in very low cogging which makes this servo suitable for high resolution applications such as tight tolerance CNC machining. Like all of our motors, it is very well made.

The high quality HEDS-9100 optical encoder comes mounted on the rear shaft of the motor.

The electrical specs of this motor were called out by Mariss of Geckodrive Inc. at our request so that they would properly match the G320 and G340 servodrives.

Specifications:

- skewed rotor design - speed at voltage constant: 4200 rpm

- constant torque: 1.2 N. m - torque constant (KT): .1757 N. m/am

- peak torque: 6 N. m - voltage constant (KE): 15.71 volts/100rpm

- terminal voltage: 72 VDC - resistance: 85 ohm

- continuous current: 8.5A - inductance: 2.35 mH

- peak current: 38A - weight: 4 Kg

- inertia: 3.39 kg.cm^

CA residents pay State Sales Tax

See our other items for more CNC components



http://cgi.ebay.com/Servo-Motor-850oz-in-Peak-Torque-CNC-Router-Mill-New_W0QQitemZ160032552163QQihZ006QQcategoryZ78195QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


some other stuff this guy is selling for cnc application http://search.ebay.com/_W0QQsassZrllalonde

cheers

FPV_GTp
09-29-2006, 07:34 PM
hi

just come across this on ebay the other day

just wandering if anyone knows anything about this system for CNC application

"

Overview
The MC433 is a multi-microprocessor controlled 4 Axis 10A Unipolar PWM Stepper Controller that attaches directly to a PC parallel port. Each channel supports variable PWM control and can be individually set for Wave step, Full step or Half step. Using four ATmega168 8bit RISC microcomputers the MC433 provides user adjustable initial on time, duty cycle and duty cycle slew rate using three potentiometers to match the drive characteristics of almost all stepper motors. Direction and step commands are fed to each channel through the PC compatible parallel port interface. The MC433 is designed for high performance unipolar stepping applications. The MC433 is ideal to drive a CNC Sherline, TAIG or similar Mill with room to spare for larger CNC projects.



MC433 Hardware
The MC433 uses four AVR ATmega168 8 bit RISC microcontrollers to individually control the PWM output to each of the four motor ports. Using high speed Power SFETs each channel can sustain 10A and peak at 33A ensuring support for the most demanding stepper application. Stepper input voltage may range from 7V to 35VDC. Limit switch detection logic on each channel is routed to the parallel port connector for host software control of stepper halt. Four output control lines are available to control external relays or related devices via transistor boosted pull down logic. Power for board logic is jumper selectable from stepper motor supply or a seperate wall mount DC adapter.



For detailed technical information (pdf):



MC433 Hardware Technical Reference Manual
MC433G Hardware Technical Reference Manual



For additonal information see www.soc-machines.com .



Technical Specifications

4 Axis PWM unipolar stepper control
10A continuous, 33A peak
PWM on time, duty cycle and duty cycle slew rate settable
Wave, Full and Half step settable individually for each axis
PC parallel port interface
Individual limit switch detection on each axis (fed to parallel port)
Four control outputs (routed to parallel port)
I2C TWI Communication port for individual motor control
Expansion ports for other functions
9-12VDC in (polarity protected)
Dimensions 4.5x4.7 in


Options

MC433G

The MC433 is also available in a G version - MC433G. The MC433G includes an onboard G Code processor that directly translates G Code commands into step/direction commands. The MC433G also allows direct control of PWM settings on an individual motor basis so it is possible to use different current ratings for each stepper motor. The MC433G implements a sophisticated G Code interpreter supporting linear and circular interpolation on board eliminating the need to feed step/direction signals through the parallel port. Communication with the MC433G is via an RS-232 or RS-485 port.



The G version is available for an additional $65.



Three NEMA23 Stepper Motors

Add three SM2006B NEMA23 Stepper Motors for $95.00.

Add four SM2006B NEMA23 Stepper Motors for $126.00.



Add three SM3006B NEMA23 Stepper Motors for $123.00.

Add four SM3006B NEMA23 Stepper Motors for $163.00.



Shipping for Stepper Motors is an additional $9.50.



Warranty

The MC433(G) comes with a 90 day warranty and a 14 day return policy. If not completely satisfied simply return the unit in the original packaging for a full refund (less shipping charges). Canadian customers will be charged 6% GST and BC customers 7% PST.



This is a new unit direct from the manufacturer and includes warranty and technical support. . "

FPV_GTp
11-22-2006, 11:10 PM
wish my cnc lathe can do some of these operations http://www.youtube.com/watch?v=pkdzN4X1SrY

http://www.youtube.com/watch?v=Rf66UlG17c8

some of these machine are awesome http://www.youtube.com/watch?v=6wK87SMAgWQ

http://www.youtube.com/watch?v=2maK44D5fQc



metal spinning is interesting also http://www.youtube.com/watch?v=Gwrk0SwDJhI

http://www.youtube.com/watch?v=txXsIs-oT3U

Adobe Machine
11-23-2006, 10:38 PM
cool stuff..How is your project going ?

Adobe (old as dirt )

FPV_GTp
01-10-2007, 09:34 PM
hi

sorry for the delay in my thread

been on holidays and bussy at work also

found a few new contollers also http://www.motioncontrolproducts.co.uk/?osCsid=ceb76eb2c6a7a90f884c043f390dc082

I better get cracking and start fabricating my bracketry

still havent purchased anything but just enquired a lot , it is amazing the price veriation on components from seller to another

this year i will set a time to complete the the irst lathe conversion

was hoping to deal with the guys from http://www.cncteknix.com/portal/index.php keep the Australian money in Australia i suppose but they take ages to respond even on a telephone call back. And very expensive compaired to other peoples products.


lets see what happens

cheers

FPV_GTp
01-10-2007, 09:35 PM
cool stuff..How is your project going ?

Adobe (old as dirt )

hi Adobe Machine

at the present stage slow

i see you lathe is coming along very nicely

cheers

FPV_GTp
01-11-2007, 03:48 AM
hi

another motion controller http://ncpod.oemtech.com/

cheers

FPV_GTp
01-19-2007, 04:20 AM
more cnc drivers

http://www.dtllc.com/products.html this seems like a big unit

http://www.montek.com/cart/catalog/8-Channel-Stepper-Motor-Control-p-28087.html this one seems like a small unit

cheers

Adobe Machine
06-17-2007, 11:45 PM
Been out a little bit, but how is your progress on a CNC Lathe...?

Looks like we are back to a trip to New Zeland and Aus ,would like to say hello to the "down Under"CNC people and tip a brew or two.

Hey, I feel good enough that I did a quick turn in the 34 Coupe..Wife had three heart attacks when she witnessed the front wheels off the pavement , almost got restricted to the area ..Hopefully we can see some Aus Rods when we are there..

Hope all is well: Adobe (old as dirt)