Quote Originally Posted by m.marino View Post
Build is going well and looking at adding a rotary table as a fourth axis. Anyone got experience in converting one from manual to CNC? If so what motor is most likely best to do this with. Looking at either a 4" or 6" diameter table. Any and all input would be seriously appreciated. Also looking at converting to ball-screws for all axis' as well and thinking that 12mm would do my well for that.
I just started writing a reply to this then realised that I'm a bit too late. Nevermind I'll say a little anyway...

I converted a 6" vertex rotary table to use as a 4th axis. It was easy enough to machine a bit of 3" aluminium bar to fit on where the handle/dial used to and hold the stepper. It's very sturdy, however the 90:1 ratio makes it a bit slow to turn. I think the stepper has worn the worm drive prematurely since the backlash has increased a lot from new.

A while ago I started making a faster 4th axis which I've posted about elsewhere in the forum. That's using tapered roller bearings and will be driven by a stepper via a belt, so will be faster and also strong.