I've seen many videos and online site talking about how people have turned their manual lathe into a CNC lathe. But has anyone actually made a CNC lathe from scratch?


Also I think it would be cool to use some of these high power, high RPM servos to make a lathe/mill combo.
Something like this....

I think it would be completely do able. Provided having a mill to machine the motor mounts and what not. I think the toughest parts would be creating a very rigid base and tooling arm that won't be vibrating much. I think the same principles for RoGR/any of the DIY conversions could be used for the movement.

Material wise, I've never done any lathing (except back in 7th grade shop class) but I imagine a DIY one could be done fairly simply if you were looking at just doing something like delrin sliders for supermoto axles (beings you've got yz400 in your name, I assume you know what those are) If you're talking about something like stainless steel or threading or any of that fun stuff, then I imagine the design would take a lot more design critique.

Then again, I've used a drill press, chisel and a hack saw blade to make a couple random pieces...so my sense of accuracy/safety isn't all on par yet with CNC.

Something like that machine though...that is just amazing. I'm sure someone could make one, but that's way beyond me. I'm still trying to grasp the hex cutting. In comparison the 3-axis mill is quiet simple...From what I can tell that machine had independent control of x, y, z, the spindle, and 4 tools.

Bridgeport went out of business back in 2002 or so and had a giant auction of their parts inventory. Most of it wound up on eBay over the next several weeks.

Fresh out of trade school and having a wild imagination, I scooped up many pieces for both a CNC lathe and mill. Ballscrews, roller bearing linear rails, a couple of tool changers. Later on, I added a couple of 40 taper Gilman block spindles. I'm likely sitting on $50,000 of retail priced parts.

So, what's the holdup? Afraid of killing myself and wasting $5K on a rig that can't hold 0.010" tolerance.

Small CNC rigs, like the NEMA 23 based units, output only so much power and are expected to be hobby based. This means if something fails you aren't going to have a 20 pound chunk of steel being thrown off a 10 HP spindle. Also, the tolerances aren't anywhere near commercial-quality, nor are they expected to be.

About all I can offer, other than a crazy tale of a guy gobbling up Bridgeport pieces for pennies on the dollar, is a word of caution: be careful. CNC machines cut via climb milling and put a great deal of pressure on the feed mechanisms. I've read up a fair amount on these projects - zero-backlash ballscrews should be used if any real power is transmitted through the cutting tool. Threaded feedscrews have play in them can wreak havoc and cause serious crashes when used in a climb milling application.

Ballscrews can be found on eBay without too much trouble but finding the correct bearing blocks is nearly impossible. I looked for years to find some for my units and finally gave up trying.

Good luck out there - post pics when done.

Regards,
J. Elliott

Here's a couple on CNCzone...
http://www.cnczone.com/forums/showthread.php?t=27031

Good lord! Look at the size of that screw!


http://www.cnczone.com/forums/showthread.php?t=51688



I bet there's more but this'll get ya started. To me it looks like a DIY metal lathe is much more of a "lets see if I can do it" project than a "I can make it myself for less money" project.

It might be easier to use a body from a low cost wood lathe and just bolt your liner rails on to it and perhaps re do the spindle setup with a new shaft and a cogged pulley for a large servo drive motor.


Click to view attachment

I don't know if this one is made of real heavy metal or if it is a toy.

That may be the coolest thing I have EVER seen.

I'll take three

-out

well this one is pretty plain, and as a matter of fact there really isn't a lot of info, but pretty interesnt to see the videos they do have for it

DumpsterCNC youtube channel

Well...... the new version with the turret tools is pretty BA