Gold filled repair

I have a request for the repair of a 14k gold filled pendant, which
is a first for me. I was planning to use 14k solder, but am
concerned about the base metal alloying with the gold. What are the
precautions that I should take? Thanks.

Jamie

Hi Jamie;

I have a request for the repair of a 14k gold filled pendant...
What are the precautions that I should take? 

If this is an antique article, it’s likely to have some assembly
using a low temperature lead or tin based solder, which means you’re
pretty much stuck with doing repairs using same. You can solder gold
filled using a low temp gold solder (easy or ultra easy) if there is
no lead or such on it. Harder solders willl tend to make the
underlying base metal blister and make a mess. That said, older
articles often have corrosion penetrating the seams and traveling
deep into the base metal, which makes it difficult to get any solder
to flow on those areas unless you can grind down to fresh metal.

David L. Huffman

Hoover and Strong makes a gold coloured silver solder that i believe
comes in easy flow temperature - that is one option but prepping the
surface is the trick- you should use a heat protectant on either
side of the join ( igor brand " heat shield" is my personal
favourite! though wet wadded newsprint paper works almost as well as
it protects any stones beautifully and the water left after wringing
the wadded paper is sufficient to allow for a quick," hit-and-run"
soldering operation that insures the base metal generally brass, is
not affected nor time enough for the gold layer to separate and
blister or bubble up so to speak- nonetheless, any good heat
shielding compound available from your local jewelers or any welding
supply store in paste form- DON’T use the spray types as they are
insufficient for brazing operations and mostly designed as
"anti-splatter" agents when using flux core wire, or otherwise rosin
type fluxes and not disturb the gold surface at all. If the piece is
severly scratched or showing definite signs of wear you may want to
turn down the job, or explain to the customer that the possibility
of the piece needing plating after the repair is quite high (and of
course the costs involved revealed!). The main thing to remeber is
that it is (GF) a layer of precious metal on another metal: it is not
sintered to it and the ease at which it separates at a temperature
appropriate to flowing is great. Going down to the base metal is
another approach but then colour matching becomes the issue and is
almost impossible as most gold filled appears a richer colour than
the 14/20 or 12/20 indicated on the piece if made after international
metals stamping became standardized.thus using a silver solder which
flows at a lower temperature than the gold karat most closely
associated with a given piece…

Good luck!!..rer

Usually its not a problem to use gold solder. My preference would be
medium, hard is too hot and easy doesn’t give the best control.
Years ago 6K solder was used but I found it unsatisfactory. However
sometimes GF will discolor so use a good firecoat. Best bet is laser.

You’ll want to do the least polishing possible. Sometimes GF just
goes bad no matter what you do, so there remains the possibility of
gold plating the piece just to get an even color, which may or may
not be the original color. I have run into pieces that polished out
redish. Pain!

Make sure you disclose the possible bad outcome.

wet wadded newsprint paper works almost as well as a heat shield it
protects any stones beautifully and the water left after wringing
the wadded paper is sufficient to allow for a quick," hit-and-run"
soldering operation 

First of all, thanks to all for the many tips. As a result, I was
ultimately successful with the repair. Yeah!! Second, I giggled
about the wadded newspaper being used as a heat shield. I learned
using toilet paper for the same purpose. It always struck me as the
most unusual purpose for toilet paper, but the giggles were because
one fella in our bench jeweler’s classes couldn’t get the
“hit-and-run” part right, and invariably ended up with a nice little
bonfire on his bench.

Jamie

If wadded newspaper and TP make you giggle, you’ll blow milk out your
nose when you find out what I use as a sweat-band/comfort pad on my
OptiVisors. I’ll give you a hint: It comes with its own adhesive
strip and it has wings! And it really absorbs sweat!

Noman

Norman, great use of a re-purposed product, gave me a good laugh! I
had a very shy friend who had a large surgical wound that needed a
dressing change, my wife is a nurse - she used a maxi as a dressing.
The doctor loved it, the patient was never quite sure.

Marlin in HOT Denver