On Sun, 12 Mar 2006 10:23:44 -0800, in rec.crafts.jewelry "C Ryman"
Post by C RymanThe previous thread on soldering silver plate made me wonder about soldering
gold filled wire or sheet (rolled gold). The gold would be thicker than
plate.
Gold or silver electroplate is made very differently from gold filled stock. The
plated metal has precious metal layer that's mere microns thick, while the
mechanically laminated gold filled metal has a layer of gold thick enough to be
described as a fraction of the total weight. Common are things like 1/20 or
1/40th of the total weight of the metal being the precious metal layer. That's
not just thicker. That's a LOT thicker. When you heat up plated metal to
solder it, there are often one or more intermediary electroplate layers under
the precious metal as well, which affects the bond with the precious metal outer
layer. So soldering heat makes it more likely that a plated coating will bubble
or flake off, and even slight fire scale or oxidation then needs enough cleaning
afterwards to remove the plated layer. With gold filled metal, you still need
to be careful to use lower temperature range solders, since of course the
sandwich will have different melting points than solid metal, and you want to
minimize chances of melting or fire scale. But with care and lower melting
point solders, gold fill can be soldered just fine. The biggest concern is that
you simply have to work 'cleanly" enough that you won't then need to use lots of
abrasives to clean up tool marks, solder marks, or the like, since with that
sort of aggresive working, you can indeed cut right through the gold fill layer.
But other than that, it's totally different from working plated metal.
Peter