FINALLY started BIG_CNC_LATHE conversion

[FPV_GTp]

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]

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]

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]

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]

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]

I would go gecko's and Servos. Forget the steppers.

Eric

[arturod]

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]

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]

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]

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]

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]

Originally Posted by arturod 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/showth...ight=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