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« on: May 09, 2018, 08:59:53 AM »
My setup is Win10 HP Laptop, Mach4 Hobby, UC100, Vista Pendant,Sherline Lathe, Sherline Nexgen Mill
System does not jog correctly when backlash setting is non-zero in Mach. This affects all axis.
Backlash adjustment is applied after each jog even though direction has not changed. Sometimes, the stepper goes the wrong direction, and often the jog amount is wrong. For instance a .01 jog may go .01, or may go something less. This happens whether the jog was done from the pc jog button, or the pendant, so I believe the pendant is not the problem.
Smaller jog increments result in more erratic behavior, especially when the jog amount is less than the backlash setting (which in my case is set to .003".
When making successive jogs of .001, the movement is often .001, 0, .002, 0, .002, etc.
When stepping by multiple gcodes, like g0 z .001, g0 z .002, g0 z .003 ..... the system seems to work correctly as shown by test indicator and visual observation.
UC100 is set to 25khz, but testing with 100khz had the same result.
Backlash should only be applied when changing directions.
System works correctly when driven by LinuxCNC so problem is not stepper malfunctions or the Sherline motor drivers.
Any ideas?
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