[compunerdy]

I did not find any previous threads on this but if there are some please let me know.

I have converted a smaller 7x10 lathe a few years back but there was a lot more info on that job. I am posting here in hopes that I can get some recommendations on motor size, spindle speed control, etc..

Thanks, Tim

[Crevice Reamer]

Hi Tim. Welcome to the Zone!

If by C4, you mean the lathe with the BLDC spindle motor and the push-buttons, then Mach3 spindle speed control may be a problem. No one has figured out how to do that yet.

You WILL easily be able to control motor START/STOP from Mach though. I plan to put instructions up on my website soon.

As for electronics, these are the best that I know of:

http://crevicereamer.com/Page_70.html

CR.

[compunerdy]

This is the lathe I am referring to

https://www.travers.com/htdocs/otmt-c4.shtml

It has the 1000W brushless motor.

[Crevice Reamer]

Yep! That's the BLDC motor all right, and all that power & torque make it a very nice lathe--Worth every penny you paid for it. It has basically the same motor/spindle electronics as the Super X3 mill. Maybe somebody has figured out how to speed-control it by now.

I don't know of anyone who has CNCd this lathe yet.

CR.

[compunerdy]

Yup, I have not been able to find any posts about someone doing one.

Well one way or another I will get it done.

If anyone has some knowledge or advice on the matter I would appreciate it.

[compunerdy]

Lets start with this. Does anyone have a suggestion on what size motors to use? Or how to easily calculate the size needed?

Thanks, Tim

[leggazoid]

The first order of business is to decouple the spindle drive from the lead screws. I guess it is as easy as taking some gears out? Now will you use the stock lead screws with stepper motors? I have a C4 at work for secondary deburring work. Only mods I have done to it are a qctp and 3c collet. I don't think they will let me convert it to CNC.

[Crevice Reamer]

I have already given you the best electronics/motors choice:

http://crevicereamer.com/Page_70.html

CR.

[compunerdy]

CR..sorry, I was not ignoring your advice. You are recommending 381 oz motors for X, & Z. I just wanted to get others input as well. Obviously it is not good to have undersized motors but I also read that it was not good to have oversized motors.

Here is a link to a 10x18 machine where they used 565 in oz motors.. http://www.atron.com.tw/uwish/front/...ategory=110945

Just trying to do as much research as possible.

I will probably replace the lead screws. I should have the lathe any day now and then I will know more.

Tim

[Verell]

A C4 lathe owner wants to know.

[compunerdy]

It has been converted. I am not 100% happy with it. It has been one issue after another but its does work.

[kawazuki]

It has been converted. I am not 100% happy with it. It has been one issue after another but its does work.

Care to expand on that?

Is it primarily the actual conversion or the machine itself?
I have a C4 and its a competent machine as a manual so can't see how automation could make it worse? Just asking?

[compunerdy]

Mainly it has just been issues with the conversion. Probably most of it my fault and not the machine. I still have play in the axis, on this machine I used ball screws and they seem to be worse than the acme screws I used on my last conversion. Overall the cnc part does work but like I said I am just not 100% happy with it.

[Verell]

I'm planning on converting my C4, so any of your experience you'd care to share would be greatly appreciated.

I"m especially interested in how & where you mounted your drive motors, motor sizes & specs. Any drawings you've made would be wonderful help!

I don't expect a lot of use, so would probably start with ACME drive screws.

[TiagoSantos]

I'd think the motor sizes on a lathe aren't as critical as a mill.. Not that much weight to move around! I've toyed with the idea of converting my old Clausing 12" lathe, but I'd feel bad about converting such an awesome machine to CNC. If I happen to bump into a broken chinese lathe or something, I'll most definitely grab it and see what I can do with it