[sunward]

.... Have you tried swapping the motors from each axis, ... Also, what is the size of your current set resistor?...

I never tried to switch the motors. Seemed too much work for no reason. ( I did change the drives as stated.)

300K ohms on each driver. Checked the bands and with a meter.

Upon re-reading your post, I notice that you were running two 6 amp motors on one 6 amp power supply. Those two motors would require at least 8.4 amps ...

4.2 A /phase. The power supply was the recommendation of the supplying company. I confirmed this 2 days ago to make sure it wasn't a problem. The rep stated the unit will go as high as 8 A so should be sufficient. The fuse has never blown.