...and try not to laugh.

Contraption 1 (http://www.roque.net/site/jar.nsf/contraption1.JPG?OpenFileResource)

Let me try to describe it: As you can see, it's got more Home Depot in than NSK. A few pieces of wood and MDF form the temporary frame. I'll limp along like that until I fill my piggy bank again and buy the 80/20 aluminum frame which will be 40" x 40" x 15", gantry style.

The power supply, not shown, is a lab HP 60v/15A. The 3 axes drives are Applied Motion 3540m. The steppers are NEMA 23, +180oz from Slo-syn and Bodine. The rails are THK HSR25, 24". The screw/rail combination on X & Y are special order Thompson with Nook nuts, 27" travel, .2 pitch. Z axis is a Daedal 8" travel. The spindle is an old Precise 45K RPM that weighs a ton. Software control is Mach2 - awesome stuff.

That's it. It's my 1st attempt after about a 2 month spending and reading spree that made me end up collecting a bunch of old stuff from eBay that doesn't plug into each other. I had to use "Mr. Glue", my hammer, to help the pieces match.

Later,
Julio

Well done Julio, I especially like the bar clamp. ;) Nice little basic machine.

Garyy :D

I had that clamp in there while tightening the screws down.. I forgot to take it out. That's it, I can't be a surgeon and be leaving stuff behind.

Here's something else I've been working on.

ZZTouch (http://www.roque.net/site/jar.nsf/zztouch.wmv?OpenFileResource)

It's a way to automatically set Z to exactly 1" above the material to be cut. It works by touching the spindle tool to a sensor, which is nothing more than a piece of copper connected to a pin on the parallel port. The Mach2 macro lowers Z until it touches, slowly backs out until it lifts off the sensor, subtracts the sensor's depths and marks that as zero. It then moves back to +1".

The idea is to be able to use different material heights and tool lengths or how far they're inserted in the chuck and set all my cuts to 1" + the depth I want to cut. Am I off with this idea?

Thanks,
Julio

JR, the link isn't working.

Gary

[quote]It's a way to automatically set Z to exactly 1" above the material to be cut. It works by touching the spindle tool to a sensor, which is nothing more than a piece of copper connected to a pin on the parallel port. The Mach2 macro lowers Z until it touches, slowly backs out until it lifts off the sensor, subtracts the sensor's depths and marks that as zero. It then moves back to +1".[quote]

It is true the link doesn't work, but I have a question anyway.

If you change the tool in the spindle then how can you set the Z zero, since there are different length tools?
This is something that I would love to work out. How to make an automatic Z zeroer.
How is it done on professional machines?

Benny, most professional CNC routers that I am familiar with are setup offline. Meaning you put your tool into a preset toolholder, measure the length and enter the dimensions into a list on the control. Normally, you don't have to setup on the table.

Others use a system like is explained here, but they have a subprogram which activates during a toolchange, the bit moves over to an out of the way place on the router bed, sets the height by the sensor and the coordinates are entered in the tool list automatically.

Trent

Our machine's Z zero is the bottom of the work piece, so when you home(ours has a reset button) the machine first time in the morning, it knows where Z-zero is. Like Trent says, all the tool lengths are stored in the machine and you don't have to do anything else all day. The part thickness (as well as width and length) are in the g-code file.


Julio, why not make your macro back up the 1", but set Z to +1, then you don't have to add 1" to all your cuts?

Sorry about the link. Can you see if you right-click on it and "Save Target As..." works? You should end up with file zztouch.wmv which is a Micro$oft format movie.

If you change the tool in the spindle or the material on the table, you run the macro again. The length of the tool or how far sticks out of the spindle is irrelevant for this. The macro does this:

1. Moves Z down until it touches the sensor
2. Resets the Z DRO = 0.000, no movement
3. Adds height of sensor itself, 0.025" in my case
4. Resets DRO = 0.025" - no movement
5. Backs Z in exactly 1".

I'm hoping with this I won't have to worry about what chuck/tool/material I use. I will set my cuts to whatever depth I want to cut in, which will be a negative number. So even if I change the tool in the middle of the job, I can still be sure I will cut in exactly what I need.

Cheers,
Julio

Yes, the link works that way.

nice machine, at least you can use this to make parts for the next one.

what are you using for the spindle?
edit: never mind. I reread the first post to see your spindle info.

Yes, the idea is to build parts for itself for now.

The spindle is 1/2 HP and too fast for cutting aluminum - as I learned. I'll try attaching a couple of pics from the laser tachometer.

Yesterday I ordered a bunch of end mills from a place in CT. Very nice people and great prices. They're here: http://www.toolbuyers.com. After I cut a few parts and myself a couple of times, I'll concentrate on building a constant torque speed control for the spindle and see if I can make it run at 3 to 5,000 RPM with enough torque to cut Fortal aluminum.

L8er,
Julio

For a "Contraption" it looks pretty good! I like your "air cleaner" is that stock?

Julio: Quite impressed with the Z macro! (saw it ages ago when one of the other guys posted pics of it but the "Movie" really brings it to life!)

I bought a Z Setter which is a 50 mm high magnetic block with a touch sensor that you sit on the work piece.

I home my Z then bring the table up until it lights back it down until the light flickers then lock the table.

I then command -50z and zero the readout there, everything following this is a neg z setting.

Big advantage here for me is the work I'm doing is multiple tool changes and setup changes so this allows me to get it done quickly. (Your way looks much easier though ;) )

Invented: yes, a fan is a must down here. If you've ever been to Miami in the Summer you'll understand. I air conditioned the garage but it needs a little help especially in the afternoons. I wish I'd turned it off when I was cutting MDF the other day...

Thanks IJ. The macro is nothing really. It very simply tells Z to move up and down until it figures its set to +1.000". I'll see if I can sanitize it a bit and post it. It was written in Mach2 speak but it can probably be transcoded to other platforms.

Since I figured out how to attach pics, here's an (ugly) AutoCAD rendition of the future frame. For you reference, this 40"W x 40"D x 15"H 8020 brand aluminum frame will set me back a tad over $600 with shipping. Pretty crazy huh? It's the single most expensive part of this high tech machine. They should be ashamed for charging this much... and I for paying it.

Cheers,
Julio

Juiio -
Is the 80/20 new or used? You can find some bargins on used (good condition) and cut that price in half! Check the surplus metal (dumps). You'll find the price of fastners a bit shocking though. If you substitute off-the-shelf fasteners (like thru McMaster-Carr or others) get some more savings. The fittings are probably best as 80/20 gear, but again - used works,
:cheers: Jim

For a "Contraption" it looks pretty good! I like your "air cleaner" is that stock?

On the top of your router it looks like a round Air cleaner element for a car. Is that original? Or is that a modification? Either way, seems like a good idea. I assume it's for filtering the air flow into the router motor?

Ah got it now. I thought you were talking about the fan in the background
8- )

Sure, that's part of the spindle. It's the air filter, like you noticed. Here's a different angle that shows the spindle better. But you're right, it does look like a go-kart carburetor filter. On top of that it weighs in at about 10 lbs so I had to remove the base it came with and replace it with those two pipe U clamps.

I just received the end mills I ordered; not all of them and not the same brand (OSG) I had ordered but I'm giving the vendor a chance to correct the issue before getting upset. Now that I have some mills, I'll be trying my luck at cutting stuff. But only after I put the electronics inside a box and away from the aluminum chips... they don't like each other for some reason. Got any interesting part files I can try?

Later,
Julio

Here's my first part cut ever using the scientific method called "trial and error". This is actually my second cut since, as I jokingly predicted earlier, I first managed a cut to a finger... I'm learning the good stuff like how not to put my fingers anywhere near the end mill while it's spinning at 45,000 RPM. I'm not saying it's wrong to do this, it's just not me.

Notice the ugly cuts as I manually stepped through each movement while rusting everything with my pouring sweat. I stopped a few times to get closer which, of course, caused issues. This is the top of an electric box I used to enclose my drives. It turned out to be a harder metal than I thought. I even took the wrong measurements so it's pretty messed up.

And a couple of shots of the box with the fan on top and, yes, a dual 30 amp breaker right in the middle. Sorry, didn't have any other switch handy.

Later,
JR

Hello there,

This is the 2nd part I cut for this machine with itself. This is a two part base to hold the spindle. I used AutoCAD to draw it and Mach2 to generate the G-code.

Specs:

- The material is Fortal aluminum
- Tool is OSG end mill for aluminum, model 450-2500, 1/4", 2 flutes. Details here: http://www.osgtool.com/catalogmill.asp?ProdNum=440-2500
- Spindle is Precise S-65. It's only 1/2 HP so I ran it +/- 30,000 PRM
- Control software is Mach2. Did I mention this is awesome stuff?
- Feedrate is 6 ipm, with 0.5 ipm on Z while engaging
- Multipass with -0.05" cut each pass.

The conservative speeds and cut depths are basically for two reasons: 1. I'm a chicken and 2. my machine frame is made out of a couple of 2"x4" and MDF so I can't really push it. The low torque of the spindle doesn't help either. Oh and I managed to break a tool already by allowing the Z axis drive to fallback to 50% current while idle. Good idea while the machine is sitting around but bad when you're cutting. A more useful feature would be to have the drive detect idle by observing all axes and not just itself. Or even better, send X, Y, Z commands with every move regardless if you're moving that axis or not.

Anyway, here's a short video and pics of finished cut. Forgive the shaky hand and pesky "auto-focus", which is not.

Spindle holder (http://www.roque.net/site/jar.nsf/SpindleBase.wmv?OpenFileResource)

If clicking on the link doesn't work for you, right click on it, save to your local drive and then launch from there.

Next is the backside of these two rings so they can be held to Z.

Cheers,
Julio

awesome job julio, keep the pictures and video's coming

Here's a couple more pics on the latest stuff.

The first one is the spindle base cut and mounted on Z. It looks simple but it took quite some work measuring all and making sure it aligned with the existing holes, etc. The CAD program threw a couple of fits but I managed to make it work.

Next, I installed the emergency power off button. Not that I want to show this level of detail on the build up but this is such an important part and it also took me weeks to find a good/cheap button for the task that I wanted to share with all. The button has two mounted switches, one N/O and one N/C. And you can add a third one on the same frame. It was cheap at $16.13. It can be found here: Omron EPO (http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=444458&e_categoryid=151&e_pcodeid=65341). If I may say, in my experience Mouser's the best of the electronic providers. They give me the same quality service if I order thousands of dollars worth or just a couple of bucks.

And last but not least, my first PCB cut on the clunker machine. It was a total bear fighting with Protel and QuickCAD. I finally got it to work by importing the .DXF straight into Mach2. Did I ever mention Mach2 is really, I mean, really great??

L8er,
Julio

Hello all,

Quick update on the progress. I took the plunge and bought the 8020 extrusions. They are the 1530 and 1545 models.The frame is now 5' x 5' x 15". The nice thing about the 8020 frames is that you can reconfigure it's shape to fit your needs. I will probably shrink the X axis a bit and shorten Z a few inches so I can move my current sticks and gum machine on to the new frame. The frame's so nice, however, that I decided to purchase all new rails and screws to go with it and make it a 5 x 5 x 15 job. That will take a little piggy banking and careful removal of the crab in my money pocket so I'll have to do with the rails/screws I currently have for now. I'm looking for 3 THK brand HSR25 rails of 60" in length and 2 (maybe 3?) 0.2" pitch precision ballscrews with no backlash. Any hints where to get these?

While that's going on, I cut another PCB. Here's a couple of pics of a weather sensor I designed a while back. The whole process to cut these is still being worked out but I basically design the boards in Protel, generate an outline of the traces, load them up in AutoCAD to trim any double crossing etc and import the DXF into Mach2. The tool used to isolate the traces is a center drill type with a very fine point. The tool doesn't have any flutes but I still spin it at about 1000 RPM to get it below the copper at 0.004". The tool used to drill the holes and cut the board out is a 0.0321" end mill. I also used the same fine point tool to engrave the top overlay on the flip side. The cool thing about this is that I can make prototypes in a couple of hours instead of sending out for them and waiting a couple of weeks. Now, if I can only apply a solder mask to it I'd be in great shape...

Regards,
Julio

hmmm..not sure this is the right place to post this but here it goes:

I'm looking to purchase 4 THK HSR25 rails of 60" in length. I tried eBay but there doesn't seem to be any available over 24" or so. Does anyone know of a good (and by "good" I always mean "cheap") place I can order these?

The picture below is what I have so far on the new frame. It's 60" x 60" made out of 8020's part number 1530. The X axis will be 1545. I'll mount one rail on each side on Y and two on X with two blocks per rail. Two 60" Thomson ballscrews, each with two ballnuts to tweak out backlash, will be mounted on X and Y. I need to order these too but have been trying to figure out how in the world I'm going to turn the ends... doh!

For your reference, SpongeBob is 17" x 14"... so much for being "square pants".

C-ya,
Julio

Hola,

Below's a pic of the frame with my current THK rails (24") and Thomson rails/screws. Tomorrow, I'll mount the motors and electronics. I'll also add a bed of MDF and side walls to keep chips contained somewhat.

I've gotten a few quotes for the 60" THK rails. They range from $320 to $650 each. I'll be savings my $ and ordering directly from THK. I also have Reid Tools working on a quote for 60" Thomson screws including the work of cutting the ends down. Does anyone have a suggestion on how to mill down the ends of a 60" screw? Do I need a 60" lathe or is there a jig of sorts to hold the screws on a smaller lathe? I'm even willing to buy a small lathe and do it myself if that would be an option. Any suggestions?

Later,
JR

And more pics... Now with motors and electronics installed. I added some MDF to try and keep the chips contained. If I may say, I hate working with MDF. It could be that I cut it at a too slow feed rate or using the wrong tool but the dust that leaves behind gets everywhere.

I also upgraded my router to a big daddy Porter Cable 7518. I haven't cut with it yet but it looks pretty capable. I basically made a larger version of my previous router base and added the 4 notches on the inside the PC router needs.

For those interested, I dissected the router fresh out of the box. It's a universal motor with a speed control based on the Atmel U2010B phase controller. It keeps the speed steady by reducing the voltage and watching the amperage consumption. If the amps start to climb, it assumes there's more load and it increases the voltage. One important feature is that it makes sure the amps don't go over 15 thus saving the windings. My future plan is to take the controller out of the router and drive it with my own controller using PWM / DC instead of AC with the goal of automating speed selection and reducing brush noise.

So, the machine is the same 24" x 24" rails I had before installed on a 5' x 5' frame. I'm saving my pennies to order the $1,300 worth of THK rails.

I'm still looking for an answer on this:
"Does anyone have a suggestion on how to mill down the ends of a 60" screw? Do I need a 60" lathe or is there a jig of sorts to hold the screws on a smaller lathe? I'm even willing to buy a small lathe and do it myself if that would be an option. Any suggestions?"

Anyone?

Later,
JR

No you dont need a 60" lathe. It can be done with a smaller lathe and a steady rest. See http://cnczone.com/forums/showpost.php?p=16627&postcount=10 for how kong did it. I would use a bit bigger lathe but you get the general idea. Also ballscrews are hardened on the surface to it may be difficult to turn them down. I have heard of grinding this surface off with a hand grinder then turning it to size. I have also heard of taking a deep cut to cut below the hardened surface. Now I havent done this myself so I could be in error.

Oh and nice progress too.

Jimbo, thanks much indeed! I'll contact Kong to get the details on how he did it. I was looking for an excuse to get me a lathe and this is the perfect justification. Now to agonize over which one to get...

Thanks again!
Julio

Hi Julio, the method I used is very dangerous, and you must understand that so much can go wrong. You see that piece of wood screwed to the shed door? Well, the leadscrew is supported by it! Obviously if you have a bore in the headstock large enough, then you should use it so you just have the end you want to machine poking through the chuxk, with the rest of the screw supported behind the headstock. Please exercise extreme caution in setting up your steady, if it is off by a tiny amount then the vibration from turning on the lathe will bend the screw, and may even turn it into a dangerous weapon. Like Jimbo said, most ballscrews will be hardened, so grind of the first few mm's to get down to the soft part which can be turned easily. You should also take precautions when gripping the screw in the chuck, use something to protect the threads, wooden blocks or cork spring to mind, but these may not be accurate enough. Hoep this helps anyways :)

Oh, I didnt see the block of wood holding the very end!!! I am also curious as I am planning to turn down some leadscrew ends. But if you use the bore in the headstock and turn the end sticking through won't the rest of the screw be unsupported? Maybe at low speeds this is okay.

Julio, maybe you will be better responses on the metalworking section for this.

I did find this web page that has a lot of info about lathes and setups. Still not clear on a best setup for turning down the ends.

http://www.machinist.org/army_machinetool/ch7.htm

Jimbo, you will still need to support the end, I meant the piece of wood which is holding the end, is at the left of the headstock end, rather than the tailstock end. Yes, low speed good, high speed bad!

Wow I was just reading that same doc a minute ago, Jimbo. Thanks both of you for all your help.

I'll first need to pick up a lathe which is puzzling itself but thought to turn the screw while scarifying the length that goes into the chuck.

Thanks,
Julio

Here's an update to the project. I got me two Thomson .631" x .2 screws 6' in length. I tried to get them cut by the supplier but they wouldn't do it so I bought a 9" x 20" lathe (I needed an excuse). I also bought a few flange bearings for the end supports and to use while cutting the screw on the lathe. I initially used the steady rest on the lathe's bed to support the screw but found it easier to work by mounting the steady rest with a bearing on the back side of the lathe. See pics.

I then milled two pieces to hold the ball nut in place. The design has a way to tune backlash out of of the ballnut easily. I mounted these two pieces to the 8020 Inc #3045 extrusion I use for X axis. Again, the 8020 made it super easy to install. To tune out any backlash the bearings had, I used two collars, one on each end of the ballscrew to keep them taut as I screwed down the bearing supports. This not only took out any slack on the bearings but also made the screws a lot stiffer. It also helps preventing screw bending when under force. IMHO, pulling the screw outward on each end is better than pushing inward where the screw will tend to warp under heavy loads. If I had to do this again, I would opt for .75" or larger screws. The 5/8" screws are a bit "thin" when you run them 5' in length like on my machine.

I also cut the end bearing and motor supports. While cutting the NEMA23 mount, the end-mill broke and X lost a couple of steps. That made it really "interesting" to true up the machine with half the piece still undone. Net result is that the motor support ended up a bit skewed and needed some manual trimming which I did on the drill press - not a bad piece of gear, btw.

Here's a few pics to illustrate the description. The light on the CNC router is a gigantic LED I added not long ago. Highly recommended to really see what's happening.

JR

More pics:

JR

Good looking machine JR. Having the right too for the job really makes construction easier, and I have used (I needed an excuse) quite a few times myself.

I like to run it by my wife so I try to tie it into making something she needs/wants this makes the "go ahead" easier, and eases my conscience.

Keep post the good pics they are very informative to builders.
Hager

Thanks Mr. Chips. I really lucked out with the lathe work since cutting the end of the screws was my very first job on a lathe, ever. I have no idea what's a good speed, feedrate or tool for the lathe. I ran it at the 2nd slowest speed and took what others call "wee cuts". It was fairly easy to turn down. I thought the screw was kind of soft since the lathe cut into it with ease... until I tried to cut off the end with a hacksaw. As seen above, I had to resort to adapting a small rotary tool and using a cut-off disc to do the job.

Here's what I got for x-mas: 4 THK HSR25 rails 1600mm long, two HSR25 bearings and a tube of THK grease. See what you get for being nice all year? I gotta give it to "Santa" for outdoing herself this Christmas. I'll finally be able to have a nearly 5' x 5' mill so I can cut 2" x 2" PCBs 8-) Now, if I can only get a real spindle to replace my Porter Cable router, I'd be in heaven.

Later,
JR

Hello all. It's been a few months since any update to this project so here's a pic of the new control box. I will be taking more pictures of the remainder in the next couple of days.

I started with an old PC mini-tower case. It looked the right size and certainly larger than the previous one I had but it got crowded in there very quickly. Take a look at the picture below and follow the numbers for a description of the parts:

1. Stepper drives from Applied Motion, 3 of them side by side. I run these at 36V.

2. Case fan PWM switch. This plugs to the microcontroller (#5) and there's another one by the drives to switch the spindle fan as well. The MOSFETs can switch up to 60V@4A. Both circuits are optoisolated.

3. Case fan, 12V from an old Compaq server. The spindle fan is the same model as well.

4. USB, PS/2 and RJ45 connectors salvaged from this same PC. The front panel (on a separate pic) show these connectors

5. Microcontroller. This is an Atmel Mega8 chip running at 16Mhz. It controls the speed of the fans using temperature feedback from a couple of 1-Wire DS1822 sensors. The temperature threshold of when the fan start spinning is programmable. The speed of the fan is set according to how far off the threshold is the current temperature. Current temp is read every 15 seconds. The fans, once started, will remain on for at least 3 mins to prevent frequent start/stop conditions while floating around the threshold temp. There's also an alarm output to a front panel LED to warn about over temperature; a buzzer will be added later. This threshold is also programmable. All programming is done via USB port and a terminal program. USB facilities are via SiLabs USB interface chip. This will also serve as the interface to a pendant in the works.

6. Parallel port breakout. The parallel cable is too long now and will be replaced later on

7. A/C outlet, not currently connected. Possibly switched with SCR or relay - still thinking about it. Underneath this plug are the 4 plugs to the axes and spindle. More on this on a separate pic

8. 250 watt PC power supply. Source for 5V and 12V

9. Optoisolator I/F to the spindle controller. This takes the PWM signal from Mach2 to set the spindle controller speed.

10. Minarik spindle motor controller. Spec'd output is 130VDC @ 10 A

11. Linear voltage regulator for 3.3V LED used on spindle. The LED is a 10MM, 35000 MCD white LED.

JR

Here's a couple more pics. The first one is the front panel. I didn't have any other material so I used 6061-T6 .125" thick.. a bit too much for panels. It has switches for the main high-voltage DC supply and a switch to power each drive individually. This is handy for those times when you need to push one of the axes by hand. There's also puch-out ports for USB, RJ-45, PS/2 and a couple more switches. The engraving was done with a .0625" ballnose for aluminum.

Since this picture, I've added the front panel USB and PS/2 ports that connect to the microcontroller inside (see above posting). The USB port plugs to the control PC and the PS/2 port (or maybe the RJ-45) will be used to talk to the Mach2/3 pendant I'm building.

The second picture is the back panel. It has Switchcraft 9 pin plugs for all three drives plus a 4th one for the sensors and gadgets on Z. On the Z cable I run the spindle and stepper motor drives. On the X and Y cables I run both the stepper and limit switches. I was anticipating some kind of interaction between the stepper drive and the low-voltage sensors and sure enough, a nice 23Khz pulse showed on the limit switch lines. This spike tripped the limit switch sensor on Mach2, though it didn't register in the "diagnostics" screen since it was such a short and fast pulse. A simple RC, low-pass filter cured it. The original plan was to run the sensors separately from the drive cable but I couldn't justify adding another 9 wire cable, plug and receptacle for just 1 sensor (I ran out of inputs on Mach2).

There's also an A/C outlet to be switched with either SCR or mechanical relay - still thinking about that. Not shown on the pic are all of the ground screws for the shields, etc. Finally, the parallel port connector that runs to the control PC and the EPO switch input.

JR

Great thread.
Any word on that macro for the spindle touch off?
colin

Hey Colin,

Here's the macro I'm using. I made this before I even had Mach2 so it's rough and unfinished but it works. Now that I know Mach2 a bit better I can see that it can be made differently but this one works for me. Proceed with caution.

Connect a "probe" to input2 on Mach2 and make sure the spindle/tool is grounded. For a probe, I used a piece of thin copper. Its important you confirm the tool is grounded by touching the probe to it manually. I have ceramic ball bearings and a plastic coupler on my spindle which isolates the tool from ground. This had to be fixed before the macro would worked. Check the "Diagnostics" screen while setting this up.

Cheers,
JR



'******this macro auto zeros Z axis using external trigger
'****** Inch version

'****** JRoque, July 11, 2004


'********************************
'Declarations

Public RunawayZ



'*********Get current environment:


Startfeed = GetDRO (18) 'Get starting feedrate



'********Set new environment:

ZZFeedRate = 10 'Sets Z feedrate
ZZCurrentTool = 255
ZHome = 1.0 'Set Z home to +1.000" off auto-zero
ZProbe = 0.025 'Thickness of probe
ZApproach = 0.01 'Feedrate on Z while moving down, towards the probe
ZRetract = 0.001 'Z feedrate while moving up once it has touched the probe
RunawayZVal = -2 'How far Z will travel down (inches) before the system asks: "Where do you think you're going, Mr?"


'*************************************************************************
'*************************************************************************
'*********************** *********************************
'*********************** MAIN SUB *********************************
'*********************** *********************************
'*************************************************************************
'*************************************************************************


SetCurrentTool(ZZCurrentTool)

Code "F" & ZZFeedRate


Call MoveZ

If RunawayZ = False Then
Call SetDRO (2, ZProbe) 'Make the DRO = to the thickness of the probe
RestoreSub 'Reset the feedrate to prior value
Code "G0Z" & ZHome 'Move Z to it's new "home" position
End If




'*************************************************************************
'*************************************************************************
'*************************************************************************
'*************************************************************************
'Move Z

Sub MoveZ

While IsActive(19) = False '19 means that probe is connected to input2
'18 = Input1
'20 = Input3
'21 = Input4

'Lower Z
CurrentZ = GetDRO( 2 )

'Subtract (ie: move towards probe) ZApproach to current Z position
Code "G0Z" & (CurrentZ - ZAPproach)

'Loop here while Z is moving
While IsMoving()

Wend

'Runaway safety
If CurrentZ <= RunAwayZVal Then
RunawayZ = True
Exit Sub
End If


Wend

'Z has touched probe
Runaway = False
Call Backout

End Sub
'*************************************************************************
'*************************************************************************
Sub Backout

While IsActive(19)


'Slowly backout up until the probe disconnects
CurrentZ2 = GetDRO( 2 )

'Add (ie: move away from probe) the ZRetract value to current Z position
Code "G0Z" & (CurrentZ2 + ZRetract)

'Loop while Z is moving
While IsMoving()
Wend

WEnd

End Sub


'*************************************************************************
'*************************************************************************

Sub RestoreSub

'*********Restore environment
Code "F" & Startfeed

End Sub

Ok, here's a couple more pics and a link to the full description of my new spindle.

As seen from the log pictures above, I tried a Precise S65 spindle first and had ok results. The spindle is a great machine running at 45K RPM and very low runout. The problem was that it's only 1/2 HP and it was choking on the stuff I wanted to cut. I then moved to a new Porter Cable 7518 but was disappointed with it's performance. It's loud, hot and, at least mine, has .002" runout. The PC is fine for what it was designed for but it didn't work for me in my application.

So, I decided to brew my own. I started by purchasing the best and largest bearings I could afford. I then went shopping for a cylinder where to mount the bearings and ended up with a raw piece of stainless steel. After reading all I could on different tool systems, etc, I decided on a design and started cutting. The project took about 5 or 6 weeks end to end and it ran about $150 in parts.

You can read the details (http://www.cnczone.com/forums/showthread.php?t=7004) on this project and see how it built up to the finish product. Dimensions and other specs are also there. This is a short video clip (http://www.roque.net/site/jar.nsf/runout.wmv?OpenFileResource) showing the runout

Current challenge is adding a set of three wheels to control the machine manually. This has taken longer than I thought mostly due to coding issues on accurately reading the mechanical rotary encoders. More on this later and hopefully more pics on the entire machine as is now.

JR

Wow! That is pretty impressive!

SS is supposed to be a real bear to work with. That run-out looks pretty good to me, but what do I know IANAME... ;)

Pretty cool, Where did you get the bearings?

WOW also,

Great work. I have tired many times to make percision parts and it is tough! Great job. What is going to be running it?

taus

JavaD, IMHO, SS is one of the best materials to work with. Aside from the hot and stringy 'chips' that I got, it's absolutely predictable and machines great. Of course, I don't know what I'm talking about since the spindle was my second lathe experience ever - but I just love SS.

DieGuy, eBay baby, eBay 8 - ) You can still see the bid (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3863730568&ssPageName=ADME:B:EOAB:US:6) on eBay for the next few days. I later contacted the guy and bought two more.

Taus, it took a LOT of patience and help from this forum. Its definitely not perfect and I'm sure luck played a big role (judging by the runout) but it was worth it. Check out the full details on the link above and you'll see I basically kicked, bit and spat it to make it work so I'm not claiming any talent here.

Later,
JR

Oops forgot: It's being turned by a threadmill DC motor. Pretty good so far actually.