A question for those in the group who do or plan to do 4th axis work. I am designing and prototyping a new 4th axis rotary fixture for release to the hobby market. It will offer either a #3MT / backplate spindle(for chuck mounting) or else a R-8 taper for collet work. I may offer it with a 5-c collet taper as well but it will be more expensive. It will be horizontal only orientation and offer a tailstock for long pieces.

My question regards the required resolution others feel they need. Typical rotary tables use a 72:1 worm drive. I am proposing to utilize a 30:1 worm drive that would yield 48,000 steps per 1 revolution via 1/8 microstepping. This translates to .0075 degrees per step or @27 seconds per step. Using a X10 Gecko G201 drive would yield 60,000 steps per rev., .006 degrees per step or @21.6 seconds per step.

I personally can not see the need for finer resolution than that, but I may be all wet on the subject.

Feedback and/or prior experiences are appreciated.

Thanks for your time!
Ken
KDN Tool