A wonderful product for soldering filigree is powder solder. This is
a product that is used throughout the industry for doing this type
of work. There are many other applications for powder solder such as
sweat soldering all in one operation, but filigree is a prime
application for the powder. You use Handy Flux and not a liquid flux
when working with the powder. The flux needs to stand up to the job
and not burn off quickly. As was mentioned in a previous post, one
of the orchid members grinds off some solder to make it into a
powder or very, very small chips and places it a the site to be
soldered. The already made powder solder saves you the time and
effort of making you own. All temperature flows are available,
including extra easy. You had thought of soldering this type of
construction in a kiln. This would work only of you have an inert
atmosphere. It will not work in a regular kiln.
BUT… you can get the solder into all the nooks and crannies,
that is an advantage of this type of solder since it is made into
such fine particles. The heavy duty flux melts slowly as long as you
do not overheat all at once, the powder stays in the flux and when
it attains the proper temperature, it will melt. I have not tried
to do the powder with a liquid flux in filigree, but the liquid flux
just does not stand up to the powder as a general rule of thumb.
I suggest that you work on a tripod with a screen and from the back
up and apply the heat to the back of the piece (the filigree work is
on the front). Then, just as you are seeing the solder start to
flow, quickly go to the top of the piece. Since solder goes to
heat, it will flow into the spaces as you direct the heat towards
the areas that you want to be attached. Heat evenly from the back,
you can direct just a little to the side, pulling the solder into
the joins you want to make. It is a learning curve to get the
correct temperatures so your piece does not melt. By putting the
heat on the thicker part of the metal (back), you are able to bring
the piece to the proper temperature without putting direct heat on
the very thin wires of the filigree. Then, when the solder is
ready to flow, you are ready to direct it into the proper place.
Remember, you must have a good fit. No solder fills large gaps.
Beth Katz
http://www.myuniquesolutions.com
Paste and Powder Solder for Jewelers and Metalsmiths