Lately I have been having lots of problems accidentally
melting sterling silver bezel when trying to solder it to a
sterling silver pendant base...I use a little torch oxy/propane set
up. Today I was using a number six tip, but have had the problem
when using other tips as well.
A #6 tip is overkill. Use a #4. Use a #3 if the pendant base plate
is particularly light, 24-30 ga. Your flame should have three
distinct zones in dim light. A bright blue inner cone, followed by a
yellow cone in the middle, followed by an outer cone of blue/green.
Aim for the area between the inner and middle cone to touch the
metal, as this is the most efficient heat concentration.
I use pripps flux and medium solder.
Pripps is an effective firescale inhibitor, but you need to use an
additional flux. Try Batterns or Handi-Flux in addition to your
...I heat the base and the bezel from the top. I try not to
heat the bezel directly. The bezel seems to melt just as the solder
With silver, remember your whole piece has to be up to a consistent
heat level. It radiates heat like crazy. Concentrate your flame on
the base plate as you have been doing, both around the outside of the
bezel and the inside of the bezel, but not on the bezel itself. It’s
thinner gauge material and melts more easily than your heavier base
Remember these things also:
If your solder balls, you have surface contamination. Make sure your
metals are free of tarnish, oil and dirt.
Make sure your joining surfaces are flat. Solder cannot jump a gap.
File both the bottom of the bezel, and make sure your base plate is
level and hasn’t been distorted by heat expansion.
If your solder has pits, you’ve overheated it. Cut back on your
oxygen, or make sure you’re heating away from the join, concentrating
on preheating the heavier base plate first.
If you flux looks brownish or blackish, you have contaminated your
piece with soot. Cut back on the gas.
If solder is clumpy, you have either underheated or used too much
Are you getting a draft? A draught of cool air across your piece can
often draw away enough heat to affect your soldering.
Make sure your solder is really solder. This is something that
happens even to old pros. Occasionally we pick up a piece of wire or
sheet we think is solder, and it’s actually a metal masquerading as
solder. Groan! The first thing I do when I get my solder in is to
mark it. Sheet solder is marked all over on both sides with a sharp
awl with the type and color. Example: #75, #70, 14kyh (14 kt. yellow
hard), 14kym, 18ky, 14kr. Chips are put in film canister tops on my
bench (keeps them contained and can find it easily), and when I’m
done with it, the extra chips go in the film canister itself, which
is marked with the type in enamel pen. Wire solder is kinked on one
end of the coil, and the piece I cut off, to let me know which temp
it is: a square for extra hard, a double kink for hard, single kink
for medium, circle for easy.
And finally, find a pro, whether jeweler or rockhound, whine and
wheedle your way into sitting in while they’re working. Observe.
Good luck. From an old hand who learned the hard way, and found out
it’s a lot simpler to learn from someone who knows what they’re doing.