Bob,
Backlash is just the non-movement of the axis. The value you use has nothing to do relative to radius or diameter
mode. So if the X has .0022 non movement then that's the value you input in the backlash screen.
My x axis has .004" also i also use 60% as a backlash speed.
Let me explain:
The z has done a rapid ( it is not returning at the F feed rate which was used to cut the thread) back to it's starting
location. In the program i think the distance is 0.1" in the plus z direction, so lets call it point "A". Now when it reaches point "A" the z comes to a stop. You defined to Mach that there is non-movement via backlash in your configuration. So MACH is smart and thinks "before i let the Z travel to do another thread" i need account for the non-movement by macking the stepper turn some. Thus the stepper gets pulses to turn enough to take out your .0022 inches and lets call this "B". Now when the stepper rotates for that small amount, it can rotate at your max velocity or a percentage of the velocity. I just use a value of 60%, there is a setting in config>shuttle wheel setting>shuttle accel which affects how fast the stepper will rotate also. Now the Z is at point "B", it gets a signal ( that index pulse ) from MACH to move and should arrive at point "C". Point "C" is a point realtive to the thread, and thus the next thread cut is done.
So, return to the start point "A", squirt some clorox on the tires and smoke them soft and sitting at point "B",
rev limiter and line lock on......red-yellow- GREEN....., pop that clutch and let them horses go wild, off to and cross point "C" and the parachute opens at "C" taking care of what needs to be done after the finish line.
OOPS, I lost the race, disqualified, and hit the dirt bank. What went wrong,
dam i was running for brass pink slips.
The little vw bug beat me!
Think i need to look at what is happening on his end.
RICH