I agree. Great lesson to be learned. ALl of our young engineers (and some of us old ones) need to remember those types of things. As well as how is it being tested. Or more importantly, are they following proper test procedures. I've seen circumstances where the test is being done wrong. Follow the process all the way through.
For starters, the technician should not have been grinding the test piece, because that in itself makes the item non-representative. So there would be no reason to expect that a ground part would not fail.
A final part of the design engineering task set is to provide the description of the means to prove that the product meets the required specifications, which would include a description of how to produce the test parts. Of course just cutting a part by any method is probably going to compromise the accuracy of any test results, so a better choice would be to design the test to fit the part. That may not be the easy method, but then the best way to do things is seldom the easiest way.
I liked the article. A good lesson for young (and old) engineers. You need to understand from the beginning to the end what is happening to parts that are being tested. Anything that is not the production process should be verified because it can be causing false results.
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