In article ,
Clive Page wrote:
For the 14 mm hole I bought an "HSS Balcksmith Drill Bit" said to have a
reduced shank (item 73936). There's no information either in the
catalogue or online as to the diameter of the shank, but the
illustration shows the shank to be *much* smaller than the drill. So I
got one - it's in an opaque package so I couldn't inspect it in the
shop. When I got it home I found it to have a 12.5 mm shank, so the
transition in size from shank to drill is barely perceptible. I didn't
have a chuck that would take a shank that big, so I could use it only by
grinding the shank down to a sensible size (not easy with my primitive
grinding skills).

IIRC, reduce shank drills are commonly 1/2" nominal. This is or was the
standard max for that size of chuck. A device fitted as standard with a
smaller chuck normally wouldn't have enough power for a larger drill.

--
*Real women don't have hot flashes, they have power surges.

Dave Plowman London SW
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