A couple decades ago, I ran across a handfull of self-tapping screws. They were like sheet metal screws, but with skirted hex heads. These were about 1/2" long and 1/4" dia. I'd seen them used with a special head on a drill motor, it having a hex chuck that would ratchet when the screw bottomed out. What amazed me about these was the fact they where not only self-starting AND self-tapping, but they where pretty damn hard. In experimenting, I discovered they tapped and screwed into an old BSA motorcycle frame like it was soft pine.
I now find myself in need of something like this and was wondering just what, exactly, do I ask for when I go down to the hardware store.
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