Hello all-
I've been a long time lurker of this site and I've been thinking about/designing (and doing some building!) cnc's for a few years now. I'm trying to put together a small, high resolution cnc laser cutter and can't decide on the most appropriate linear motion system. I'm looking for ~4" of travel in the X and Y (no Z) with a resolution down to around 0.001mm (1 micrometre). So far, I've been mostly designing around steppers driving small, high tpi leadscrews. I've been having trouble sourcing high tpi scews that will give me enough travel. There are a few companies that make 200tpi screws mainly used in (I think) scientific apparatus, but the few that I found with enough travel were prohibitively expensive. McMaster sells a 41.7tpi miniature precision acme screw and, with microstepping, I think I can get the resolution I'm looking for.

I though I'd pose the question to the community here. Is there a better way to do it? I don't have much knowledge or experience with them, but would a servo system serve me better than steppers? Being a laser cutter, it won't be subject to nearly as much force as a mill would and, for my application, it can be run pretty slow. Could I get away with another drive system altogether? Maybe belts or a rack and pinion?

Thanks for the help