Have a 4x8 plasma table im building. Driving with 3/8" wide GT belts at .2" pitch. Heres my problem.

I run the gantry up against my dial indicator and if i program to move 20", 50" or whatever distance away from the indicator and then come back the same amount the machine will come back and stop within .001" every time. If i move it up against the indicator and then program to move in increments of .100" moving the same direction it is not consistent. First move might be .090", next move will be maybe .085", next move will be like .105" and so on. If i reverse direction there is a lot of backlash to deal with, but moving in same direction i would expect the machine to be accurate within at least a couple thousandths. One motor step = .001" at 10 micro steps which im running.

Are there any settings in Mach3 that might need some tweaking?