Erratic Axis Movement with Backlash Compensation

[swdjeff]

I've enabled backlash compensation on one axis in UCCNC and this is the only only axis with issues.
When I advance in only one direction with .001 steps, my dial indicator shows alternatively an advance of .001 and a backtrack of (Backlash Distance - .001).
(The happens with both arrow keys and typing Gcode into the MDI - y0,y.001,y.002,y.003,y.004...)
It is very repeatable and I even end up in the same places on the dial indicator when I change directions.
I do notice that the DRO jumps around on each step.

If I turn off backlash comp the DRO advances to the next step directly and the indicator shows movement of .001. (with some backlash if I change direction)

I've tried different Comp. Acceleration values but see the same results.

Another symptom that I see, but might have trouble describing is that when contouring Y-Z trajectories (X slices) I notice slight bobbles occurring at the same Y values (the compensated axis). They do not appear to occur in a pattern I can identify but seem to be around the magnitude of the backlash compensation value. The trajectories alternate directions with each slice, but I have not determined whether the bobbles happen in both directions.

[cncdrive]

The DRO does not show the backlash compensation at all, so I think your problem report is likely not accurate.

[swdjeff]

I agree that it is not showing backlash compensation
When compensation is on, the values displayed (at least the last two digits) on the DRO for the axis move all other the place with each step before settling on the correct value for that step.
With if off, the DRO advances directly to its next step.
Would it be helpful for me to try to take a video?

[cncdrive]

Yes, I think a video would be helpful.