This just for my curiosity, I'm not about to go CNC.
I assume that the lead screw is controlled independently of the spindle, with its own motor, not through a spindle-linked gearbox. Or, is it linked & the gear selection computer controlled?
If a separate motor, there is a huge range of speeds required: feed from .0025 to .250 is 100:1 & that's multiplied by the spindle speed range, say 200 to 2000 is 10:1. 1000:1 total. How do they do that?
If not a separate motor ... never mind.
Thanks, Bob