Re: A big ol' chunk of delrin

"Mike Spencer"  wrote in message news:87zffvzsf6.fsf@enoch.nodomain.nowhere...
I once made a (finger) ring from pattern-welded mild steel and a piece
of VW Beetle front suspension torsion spring.  File glided off of it
as if it were glass.  Put it in the coal of the wood range and left it
overnight as the fire died.  Next day, it filed nicely.
Those yard-long VW spring leaves can be clamped in the vise and bent
180 and will violently spring back.  Heated to red in the forge and
cooled in air on the bench, can easily be snapped of by hand with a
very few degrees of bend.  Glassy-hard.  Air-hardening alloy.
So, good lo-tech annealing trick.  Dunno about rock drill pipe, though.
--
Mike Spencer                  Nova Scotia, Canada
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This piece snapped without any evident deformation. A hacksaw cut it easily enough that I risked finishing with the bandsaw on the lowest speed. A search suggested it might be in the High Strength Low Alloy family. I mentioned it as a source of machineable higher strength steel at hobbyist size and price. I also have a used snow plow cutting edge to try.
jsw