This article explains how to use Mach3's Screw Mapping feature to reduce error on the Z axis of my RF-30 mill/drill. I have to admit, this adventure sure made my head hurt! But the results make it all worthwhile.
Screw Mapping will improve the accuracy of my RF-30 which uses a relatively sloppy gear train plus rack and pinion. Think what it can do for those with ball screws.
If you are interested, please see:
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