Does anyone know is CMM's us ball screws.  I would like to scrap the controls on an old CMM, and retrofit it with Mach3 for use as a cnc engraver/router.  Is this plausible?

Thanks

I have never seen inside the bellows covers on one of these but due to high accuracy they operate at I would suspect micrometer type screw threads with anti-backlash nuts.

Tweakie.

Most have ballscrews and linear scales for feedback and accuracy, your problem will be reading the scales for the measurements.

Most of the later ones also have a 3d model of the movement to compensate for position errors, twist and yaw.

Graham

I converted an omis III CMM I bought for $500 a few years ago. It was built in 1996 and looked like a standard moving table mill. I believe it was used for video inspection of auto parts. The base is made from 5" of cast granite and the incredibly sturdy gantry is made from cast aluminum legs and a ceramic crossbeam. The granite base rests on vibration dampeners fixed to it's own steel cabinet base. This thing was made sparring no expense! The linear motion components were comprised of thk linear bearings and old fashioned leadscrews.

The fist thing I had to do after I brough the beast Home was to fix an appropriate linear slide for the z axis and mount the router. I then used some used steppers and a xylotex motor controller to power it all up. The first year I used that machine to make a few thousand dollars! Many years later I replaced the xylotex with a g540 and the leadscrews with ballscrews. The machine is absolutely incredible and is faster and more precise than my Techno lc4896 retailing at $35K!