So I'm running a 7.10.7 with an indexable head using touch trigger probes, checking some really big parts. Occasionally we switch over to check some smaller parts with lots of deep internal features. These are literally scaled down versions of the larger parts. To do so I have to add a 100mm extension between the probe body and CMM head. Recalibrate all the probes in my rack. Update the loadprobe command for like 10 programs using 4X40_Probe to LONG_4X40_Probe as an example. Takes about an hour to an hour and half I guess. I do this when ever its needed which is about twice a month sometimes.
So I had the idea of keeping the extension on the CMM at all times. I wrote a program offline and I was able to clear my large parts by indexing to A45B0 to move in and around my part, safely index down to A0B0 and continue inspecting. It worked offline and I tested it on my CMM last weekend and it worked amazing. I thought I solved my problems of having to come in and remove/install the extension from happening but I was wrong. That weekend when I tested my program and part it failed the some angle dimensions. I thought nothing of it and figured we would just write an NCR and just keep going. Well its been failing those same angle dimensions on every large part we've made since then.
So its been a week and I was doing some troubleshooting today. Cleaning scales, cleaning and re calibrating probes and cleaning parts. Someone suggested to recheck and failed part, then remove the extension and re test a failed part again. Well I did that and it passed the those angle dimensions. I guess the culprit was the extension? I don't understand why it would fail those angle measurements on the large part with the extension but pass them on the smaller still with the extension.
Anyway I had to email engineering and production and quality that the issue was the CMM the whole time and the CNC machine.
