Kara, Yes, you can use silver solder on steel, and you can use gold
solder too. Hard, medium, and soft. You can, of course, weld steel
if you want a really permanent steel to steel joint.
I often use the same white brazing flux that I use for gold when
joining steel to gold. The flux I use is for nonferrous metals, but
there is also a similar flux available specifically for iron and
steel. I have a flux that I like, called âBlack Fluxâ that is made
by Englehard (available at Metalliferrous in NYC) that is great for
high and prolonged temperatures.
You can pickle a steel/silver or steel/gold combination in your
sodium bisulfate pickle, if it is fresh. If it is old, chances are
that it will have a lot of dissolved copper in it, and that will
plate onto your piece. Mild steel, the type you will probably be
working with, will etch if left in the pickle too long, so monitor
the progress of your work in the pickle.
As far as blackening or oxidizing the steel, many things will work.
Heat will blue or blacken the steel. There are also chemical
solutions, used either hot or cold, for bluing, browning, or
blackening steel. These are often used by gunsmiths, and I have
found these chemicals to be the most reliable. Gunsmiths are VERY
fussy about the quality of the patina. The cold bluing agents are
the easiest to work with on a small scale, and will give more of a
black color than a blue. You can keep applying the chemical until
you get the desired color. Hot patinas are usually applied by
dipping the piece.
Stainless steel will not oxidize. Use mild steel. You can use scraps
from a body shop, junk yard, found objects, or you can purchase new
material from a variety of suppliers. Small Parts, in Miami, is a
great resource for small amounts of metal (steel, aluminum, copper,
bronze, whatever) and they have all kinds of useful stuff, like
screws in very tiny sizes, taps and dies, gears, bearings, etc., 800
220-4242.
If you wish to make up your own patina formula, here is one that was
used specifically for steel and gold jewelry:
Potassium hydroxide..................................15grams
Sodium hydroxide.....................................640grams
Sodium
nitrateâŚ20grams
Distilled
waterâŚ880grams
Add chemicals to water in a clean, Stainless steel beaker, and heat
to a rolling boil. Simply add the piece to be oxidized into the
beaker. THE PIECE TO BE OXIDIZED MUST BE IN CONTACT WITH THE METAL
BEAKER. It is best to attach a wire to the piece before dropping it
into the beaker. Just pull it out periodically and check the
progress of the oxide. When it is as black as you wish, rinse and
wipe dry with a soft, cotton cloth.
Like any oxide, plating, or patina, this is the final finish, so
make sure it is polished and free of scratches (or textured, if you
wish) before you add the oxide finish. The oxide is quite durable,
but not unscratchable. It will only oxidize the steel, leaving the
precious metals untouched. If you do get a scratch on it, even years
later, simply re-dip in the boiling solution. You can keep the
unused solution in a tightly covered container for a long timeâŚI
kept mine for 3 years.
(The usual warning about working with chemicals, having ventilation,
and all that common sense stuffâŚ)
Iâm sure the chemists in the group can explain how and why these
things work, and will have lots of suggestions for other patinas.
The formula above was used by Cartier on their jewelry, and I have
given it exactly as I received it. I used it to repair/restore some
of their older pieces, when the owner did not wish to send them to
Europe for restoration. It worked great. I use a hot bluing patina
on some of my sculptures, as it goes on evenly over a large surface
and seems harder that the cold bluing solution. I use the cold
bluing solution for tiny details, since I can paint it on with a 000
brush.
Steel is nice to work with. For inspiration, go to
www.studionamu.com, and look at Nam Woo Choâs work. I carry it in my
gallery, and I really love it.
Have fun!
Doug Zaruba