Pat Wider wrote:

I'm curious, if a modeler just uses them to drill holes in soft
plastic toy
train freight car models at low rpm (to avoid melting the plastic)
with a precision drill
press, why pay extra for high-speed steel drill bits? It's not like
everyone is drilling holes
down into the car's steel weights.  I also have some larger carbide
tipped drills but I
wouldn't use them just to drill brass. No need.

True about plastic, but some of us actually drill brass and stuff,
Pat. The carbon steel dulls a lot faster, whatever it's being drilled
into; softens far easier if overheated (and we've all done it); and is
much more brittle, thus a slight bending by the inattentive or
unskillful drill person is much more likely to break it.
Whatever the reason, I agree with Denny Anspach's estimate of the
carbon steel bit half-life: something less than one project. <vbg>

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
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