I have tried to heat a silver piece using the submerged trick.
Doesn't work
Yes it does.
But you need a surprisingly hot flame to do it. If you’d normally be
soldering that shank in air with a medium tip on your little torch,
you might not realize that with the top under water, you’d need to
bring out a much larger tip, or even another, hotter torch. With a
little torch, you might be able to use the largest tips when burning
acetylene and oxygen, but I doubt you could do it with propane. In
my case, I usually use a medium tip on a meco midget torch, with
oxygen and propane. And cranked up to a respectable size, and
neutral, not too soft a flame. That’s a flame that, without the
water, could quickly melt the ring into a puddle, or with just a tad
more oxygen, would have an easy time melting platinum… You can find
that the flame needed to solder a substantial size shank like this
would be one you’d normally expect to be using to melt a couple
ounces of metal in a crucible for casting, rather than one you’d use
for careful soldering. Silver is a wonderful heat conductor, one of
the best, so the water will drain away the heat at a prodigious rate.
Thus the need for a really hot and not so small torch flame. I
usually use a container like an old used tuna fish can for this, and
with larger shanks, it’s not unusual for the water in that can to be
almost or actually boiling before the solder melts, and that’s even
with working reasonaly fast. if you’ve got the right size flame, it
works just fine, and the stone portion of the ring never gets beyond
the temperature of boiling water, which most stones are happy with,
especially in situations like this where they warm up gradually
rather than instantly. If you’ve got something more heat sensative,
you might need to use a larger container so the water cannot heat up
that much. The most common problem I encounter, once I’ve got the
right size flame, is that the water right where the shank sides are
entering the water is sizzling and sputtering, which can sometimes
try to blow out the flame, so sometimes I have to hold something,
like a pair of tweezers or a bit of scrap steel or something,
between that spot and the torch tip to block the spatter. One jeweler
I know made a little steel sheet shield, essentially a bit of sheet
with two slots along an edge, which she holds with another tweezer
just above the water, with the shank sides in those slots. That
shields the whole solder joint area and torch tip from water
spattering quite well.
I’d recommend that the first time you try this, you do it with a
practice plain band ring (no stone) that you make from some heavy
silver shank stock, just to get the feel of it, before trying the
actual ring. That way you’ll know what to expect.
But I promise you, it DOES work.
Hope that helps.
Peter Rowe