Reducing diameter of straight drill bits
I slightly opened up the holes in truck leaf springs that dulled my
drill bits by making a half-round piloted step drill out of O-1. I
can't find it right now but I think light blue was the right temper,
on the third try. It cut reasonably well without any back rake, using
a lot of pressure. The truck's owner and I took turns crawling
underneath and heaving on the drill.
jsw
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