Originally Posted by
GreenLead
Will has managed to get 1/10000" resolution out of his setup, although I'm not sure if this means anything...
Using my definition of resolution that figure really doesn't mean much.
200 steps/rev x 8 pulses/step x 5 revs/inch = 8000 pulses/inch
8 pulses/step refers to 8x micro-stepping. That's the way my drives are currently setup.
My ballscrews are 5 threads/inch.
So the resolution in inches is 1/8000. 1/10000 if you want a round figure. The working tolerance of the machine is no where near that figure.
2x micro-stepping with a 20 tpi acme screw is also 1/8000. If the machine is not direct drive, well.....there's all kinds of possibilities.
That explanation might be clear as mud but it is a possible explanation of the number you were given.
Ballscrews will give you a faster machine and less time spent on adjustments. For your needs and budget I really don't see a practical advantage in using them. The really good ballscrews cost big money. A well adjusted acme screw will outperform a mediocre ballscrew for this fussy work..
Anyone who says "It only goes together one way" has no imagination.