In article ,
Dave wrote:
You can certainly get 300mm long non HSS twist drills - I have a set
(5,8,10mm) bought off a market stall. I'd guess HSS might break too
easily at this sort of length.

To help prevent this happening, just pull the drill back out of the hole
to let the saw dust out. It is the saw dust that grips the twist drill
that lets the torque to go up to the twist drill's breaking point. Just
drill for a maximum of 2 inches at a time and then pull out.

I was thinking more of bending type breaking than twisting with a very
long smallish HSS.

--
*In "Casablanca", Humphrey Bogart never said "Play it again, Sam" *

Dave Plowman London SW
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