[rustyolddo]

Just put the finishing touches on my converted mini-mill. Using a Hobbycnc 4AUPC board and TCNC 4.01. Mill is set up with 5TPI ball screws, controller is 1/8 step.

I've got a simple stick font engraving file that I'm using to test. It engraves a single line of text .100' high. When I run the file the, the text doesn't end up being on a straight line it kinda rides a wave. Some letters like G, O & S are compressed or smaller than the other letters like L, F, I, etc. At first, I thought it was the backlash comp. I went and set that up on all 3 axis using a DTI to tweak it in on all 3 axiz. It didn't make a difference.

I'm running 4.01 on a Pentium laptop, booting from a DOS floppy. I disabled all the power management in BIOS. Made sure the 'Precision' was set to 0 to eliminate rounding. Reverse axis delay is 100ms, ARC factor is 1.

I'm at a loss as to what the problem is. I know the code is good as I've used the exact same code to do the work on a Bridgeport. I'm not running anywhere near the limits on accel, start & max vel and at these small movements, I doubt the max speeds would come into play.

Any suggestions?