Looks like this is something that can be compensated for in some controls, and I ran across a Mach3 plugin that handled it last night which would probe a ring gage every how many degrees and calculate compensation, so can be done. But not seeing such a thing in CNC12. At least, not in the Probing or Digitizing chapters of the documentation. I did not run a search in the PDF, but Google didn't turn up much in a quick search.
Looking over the Custom Macros doc, it looks east enough to write a macro that probes in X and A axis rotary, so I can avoid the kinematics error with my current project completely.
But it would be nice to know that Wall Following had a way to compensate for kinematic probe error, as right now I'm looking at +/-0.002" error over 360 degrees on top of backlash compensation. This pic is the average error of 3 Wall Following runs (not 10 as the pic says; bailed on that after hearing from Drewtronics), after homing, bore probing, setting zero, then running Wall Following. 1mm ruby stylus, centered 0.0003" TIR.
3 lobes are expected with this sort of 120 degree NC switch probe. Not sure why it dips so far on the right, but is consistent between 3 runs so easy enough to compensate for. Green ring is the nominal 2.2190" diameter, red upper and lower error bands.
Also, 99% sure this is the last of my questions about probing. And frankly, this may actually be a feature request.
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