Swap the pin outputs---good idea, I'll do that.

All the other Q's

Have you made sure there's no feedrate adjustment in the Gcode for the circle ? is None

Is feed overide in use on the circle ? N

Have you tried feed overide to see if it makes any difference ? Same weather F/R is in Gcode or O/ride.

Does it stall\lose steps if you jog all 3 axes together or jogging 1 back and forth while jogging others ? Jog is healthy al all speeds up to max (1300mm/min)

Does it stall immediately on the Y-axis.. or only above a certain speed ? Not directly speed related, see above but would stall at a direction change

Is it a constant loss of steps.. or a single big stall ? big stall which it usaully recovers from

Are you sure the problem is restricted to a single axis ?Y

What OS are you running ? WinXP

Have you run the mach 3 optimisation ?.. i.e. switching off unused system processes. don't know. Will investagate.

Have you run the mach 3 pulse rate test on your machine ? No. will investagate
What IS your mach pulse rate on diagnostic page.. does this match set pulse rate ? Dont know
Have you run motor tuning ? No

Are you sure your axis calculations (steps per unit) for mach 3 are correct and that settings are correctly applied. Dont know, didnt calculate but reverse engineered off a ruler.

Are all motors\settings the same ?Y

Have you tried changing the origin position of the test paths along the Y axis.Y same trouble

What happens after the stall ? would it complete the motion\cut.. or stall again ? recovers until next time.

The current limiting setup on your drives may also have a bearing on this.. i.e. is current limiting built in\adjustable.. if so how.. are settings correct for all motors.. that kind of thing..
Will triple check drive settings.


Thanks for the input . I'll report the progress if/when I ever get a day off to play