Seeing a consistent 0.03–0.05 mm shallow cut on dimple keys after about 150 cycles, verified with a Mitutoyo digital mic and the machine’s test card. I re-zero the tracer, swapped to a new 1.5 mm cutter, and cleaned the M2 jaw, but spacing and depth still creep — anyone calibrating with shims or a better datum key to lock this down?
I chased the same 0.03–0.05 and it was the 1.5 mm cutter creeping in the collet; I set a fixed 18.5 mm stick-out with a stop collar, wiped the shank with acetone, and torqued to spec — no drift past 300 cycles. > creep — anyone calibrating with shims or a better datum key to lock this down? I skipped shims; before making a datum key, Sharpie a witness line on the cutter shank and run 50 cuts — does the line move?
I’d check the Z-axis coupler set screws and the stepper mount; a hair of play there can translate to 0.03–0.05 shallow once the spindle heats up. If those are tight, let it warm up 3–5 minutes, then re-zero and test — these act like an espresso machine on temp drift. @elena_j94’s collar tip is good; do you see the same creep on the test card from a cold start or only after a dozen cuts?
And i’ve seen this come from a slightly flattened tracer tip — like measuring with a worn pencil; swap in a fresh probe or lightly lap the tip with 2000‑grit, then redo the ‘probe offset’ once the spindle’s at temp. If a new tracer doesn’t change it, the probe’s return spring may be getting weak and replacing that cured my drift.