Straight to it. All measurements in metric. Versions: PCDMIS 2013 & 2013 MR1.
We calibrated our probes, using the usual method in probe utilities. But now they are all reading wrong. Up to 25 microns too small to be precise.
We calibrated a probe last week, then we ran a job today which had a 11.000 mm bore, it measured it as 10.980. Yet a 11.030 plug gauge slips in fine. We then ran it around a UKAS verified 8.000 setting gauge and it was reading 7.975. We recalibrated the probe and ran both again, and it still measured small on both the 11.000 and the 8.000. I edited the probe file manually (adjusted the diameter size) until it read precisely 8.000 on the setting gauge, then I ran it round the 11.000 bore again. This time it came out at 11.040 (which explains why the plug gauge went in fine). We checked the calibration spheres and they are measuring fine with a micrometer (which in itself is reading fine on UKAS verified slips). We then did this entire process on our other CMM and exactly the same thing has happened. Something is going wrong between the probe measuring the sphere and the software adjusting the probe data to bring it in line with the sphere size.
So why is PCDMIS not properly adjusting itself when it measures the calibration sphere? Why does it think everything is small?
We have deleted the probes files and rebuilt them to remove any possible accumulative error, but we are getting the same issue. We have verified everything and the probes are definitely reading wrong, this isn't a "maybe the job is wrong issue". The probes aren't damaged either, and we have tried swapping them over. This error is occurring on all 18 of our probes across 2 CMM's.
