Re: Ball bearings

"The trick in
drilling these things is that you must
release the internal stresses within the ball by heating it up until the
ball bearing turns
red.  I did that using a common propane torch.  Once the ball has been
heated to red hot
let it cool down naturally....don't dunk it into cold water otherwise it
harden again or possibly crack.
Once that is done, you can drill the ball, insert whatever diam rod you
and solder it into
place again either using ordinary solder or silver solder.
You will find that after all that heating and cooling the ball bearings
come out black, but
what you do now is if you have a lathe or a drill press, put the rod
the chuck and spin it up
to speed.  Apply some very fine steel wool to clean it up  and then take
of leather and apply some Brasso onto it.  Place the leather against the
rotating ball bearing and boy do those ball bearing come back to life

	I didn't have such good luck.  Followed exactly your procedure, and
ended up with a slightly pitted surface (the oxide flaked off unevenly)
and still too hard to drill.  Eventually silver brazed to the thing and
tried to polish it but didn't like the results and never used it.  Right
now I have about a dozen 1-1/2" (+/-) bearing balls from the one of the
main shaft bearings for a jet engine, and would like to use them because
they look so neat.  Suspect that a blown cylinder gap will work much