Quite an interesting post, and on a topic that I have not studied much. It certainly required a bit of insight to understand what the changes had to be, and it is interesting that the techs assumed that the part needd to be redesigned. That is the sort of attitude that comes with not understanding just what is happening with a process. Of course, if they understood as much as the engineer then they would be designing the parts instead of testing them.
It sounds like the rotor being tested must have been fairly small for setscrews to be equal to any signifigant portion of the mass of the part.
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