Where to buy small metric counterbores
Wes wrote:
The drilled hole using a conventional hole is the pilot. The flat ground one guides on
the previous drilled hole and takes out the drill cusp.
That's just flattening the bottom of a blind hole, that's not
counterboring - where the counterbore is larger than the drill hole. Or
maybe that's called counterboring, too, even though it's a very special
case.
Bob
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