Hello all; I finally bought my own rolling mill, and have been playing
with it (which I never could do when using school’s/other people’s
mills). I did some simple fold-forming, making practice pieces first
in copper. No problem with it so far. I then wanted to make the same
pieces in silver. I followed the same proceduRe: anneal, quench,
pickle, wash, dry, fold up 'n roll. I rolled each piece through about
3-4 times (only), until I judged it was too hard to go any further
(no cracks). Then annealed again, quenched, pickled, etc. BUT: now
the mystery…the pieces were still hard! Hard as in “no, I can’t
possibly unfold this and refold in another direction and roll through
again.” Hard as in “I can’t unfold this at all without pliers” hard.
Is there something wrong with my annealing procedure, or should I be
doing it differently after fold-forming?
Here is what I did: annealed 4 pieces on pumice in an annealing pan,
heating each one in turn; quenched them when done in plain water, put
them in the pickle ( I never quench in pickle due to the steam and
fumes). Heating was done to medium red, or dark orange. Am I
annealing to the wrong temperature? Waiting too long to quench?
Compressing the metal too much before re-annealing? Every thing has
always annealed just fine before, so perhaps I have been careless
about procedure. I had no problem with the copper pieces. I tried it
over again, this time quenching each piece one at a time, as soon as
the red disappeared. I think it’s a little better, though still way
too hard for further rolling. Any suggestions? Thanking you in
advance… Lin