Great story, Glenn. Sounds like a die design problem. "Die spit" (molten metal shooting out of the die) shouldn't happen if the die is properly vented, and "dirt" shouldn't build up on the die surfaces if it has sufficient overflows. Diecasting is a complex process with a lot of variables, but it all starts with good tool design. (One question: shouldn't something building up on the die make the parts thinner, rather than thicker?)
I don't recall ever naming robots or other machines, although I have worked in shops where machines had been given names. And my father alays told me that machines are female, so no, she (the robot) didn't drink beer.
Glenn, I am very impressed by your methodical approach to the problem. Many times someone will come to one with the culprit rather than with the problem. The fact that the robot could not speak for itself was probably the reason in this case. The QC manager should have just said the parts were "bent" and left it to someone like yourself to determine what happened.
I ran into something similar with a piece of networking software. It turned out that it was the application design that was the culprit. The customer had put a network analyzer on their system and tried to lead me in that direction. The only problem was that there were almost no parameters that could be adjusted in this particular software. Once they took my suggestions about how to use existing mechanisms to restructure the software, performance was greatly improved. I even gained a reputation as the one who had solved a big problem for another company (who was using the same software). Really, it was only a couple of hours of work.
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