Taig mill with gecko g540 and mach3. Backlash is about .0005 on all axis. Measured with dial indicator. When backlash compensation is set to .0005 in mach3 for all axis, Z axis will stall when its moving when either x and or y is also moving. In other words when 3 axis milling. When this happens the Z motor locks up and the X and or Y keep going, which ever is moving at the time of lockup of the Z. X or Y will also loose a ton of steps. My origin of my part is now 2 to 3 inches from its original spot. Depending on how long the Z is locking up for.

This condition was plaguing me for days trying to re-tune my motors in mach3. I tried the gecko config file, deepgroove file, my own from a basic mach3 mill. No difference. So I went to the mill. Took my Z motor off to find its not anything with the mill. Unplugged the the motor and swapped it with my Y motor. Problem still with Z axis circuit. Swapped cables with the Y axis. Problem is coming from just the Z axis driver on my gecko g540. I tried tuning my trim pots but they will already in a good sweet spot and made no difference.

Of course the last thing I ended up doing was just turning the compensation off and well I found out that was it and that's how I've been running my mill since then. Mill runs fine without backlash compensation. I also tried playing with the amount of backlash. I set it at .001 and still Z locks up.

Why does my Gecko g540 not like backlash comp from mach3? Is .0005 or .001 compensation to little for a gecko to handle? Should I even be complaining about .0005 backlash? Its not a tolerance I require but its nice to know I have accurate parts coming out. So I'll just live with it but I would like to know if anyone else has run into this.