Re: Gecko + Servos + Taig Mill

At 22:30 25/03/2001 +0000, you wrote:

>So, without further ado, here's my question: How much power should I
>be looking for in the servos, and where should I be looking? I have
>some Vexta 125 oz steppers and they seem pretty powerful, but I've
>heard the Taig likes 200+ oz. How does this transfer to servos?

The original Taig CNC mills used 140 oz/in motors, so your 125 oz/in
steppers are in the right ball park, if at the lower end of the range. I
upgraded mine to the 200 oz/in motors recently & they make a significant
improvement. I have no experience with servos, though.

>I'd like to change the Taig over to ballscrews, so I suppose this
>should be included to get a good answer.

Good luck! There isn't that much room in the X and Y axis components for
fitting ball screws - particularly, for fitting the nuts. I suspect you
will find this is problematic & that it will involve re-machining the
channels in the X-Y table components that carry the leadscrews, or
modifying the leadscrew bearing arrangments to allow the nuts to be mounted
outside. If you find a sensible solution, I would be very interested to
hear how you do it.

The Taig CNC conversion involves replacing the leadscrews & their bearing
blocks - the manual mill uses plain bearings, whereas the CNC uses twin
ball bearings, with provision made for fitting motor
mounts/couplings. However, the screws themselves are still conventional
V-form 1/2"-20TPI.

Regards,
Tony