Motors are 200 steps/rev, set at 1/2 microsteps = 400steps per rev, with threaded rod at 20 TPI = 8000 steps per unit. I've set the motor tuning at that and the motors seems to work best with the accel and velocity at 5 to 10 %. Best of all, no more crazy cuts, I haven't measured down to the nearest hundred but the movement appears to be correct. Thanks for the help, this was driving me nutzo.