Am I the only one who got the impression on the "Where to buy machine screw assortment" thread that the OP was only talking about using an untapped hole to jam the end of the screw into (or perhaps holding it in a vise) as he evaluated how easy it was to twist the screw apart? It sounds to me like he was only testing the screws, not trying to put something together. He seemed to think that he needed screws stronger than what he had and asked if anyone knew where to get stronger ones. I too was confused by the postings on both sides until I got this idea and now it seems a lot more logical.
Don Young