Anyone else watch the remake SPC chart spike the minute the edger auto-centers and declares 0.35 mm decentration within tolerance? I kicked a -2.50 back at 10:28 a.m. and felt like I was arguing prism with a toaster — do you disable auto-center or re-block every tray to keep the run chart flat?
— do you disable auto-center or re-block every tray to keep the run — I keep auto-center on but set the centration tolerance to 0.15 mm and lock PD from the LMS; if it tries to move more than that it hard-stops me and I re-block only for ≥2.00 cyl or any prism. You seeing the drift worse on AR stock or is it across materials?
I tamed those 0.35 mm ‘within tolerance’ calls by doing a quick camera‑offset calibration each morning: ink the layout cross, cut a sacrificial blank, verify the cross in the lensmeter, then enter the X/Y bias so the system trusts the marks… Since then my run chart flattened, though I still drop chuck pressure one notch on minus jobs to keep slippage from faking decentration.
After that 10:28–2.50, I lowered chuck pressure and used fresh AR pads — killed the ‘0.35 mm’; seeing pad creep?
@karen_davis34 makes sense on tightening tolerance; what flattened my SPC was running the ring‑gauge shape-size calibration weekly so the scale stops nudging PD — mine thinks PD stands for “pretty debatable.” You seeing it more on slick AR poly?