Hi Have any of you tried, or heard of, gold plating a metal object
by dipping it in molten gold then burnishing etc the surface?
Thanks
Jack Ogden
Hi Have any of you tried, or heard of, gold plating a metal object by dipping it in molten gold then burnishing etc the surface?
I have never heard of anyone doing this. Fine gold melts at 1064.43
C (1947.97 F) and would need to be at least 100 F hotter to not
freeze the instant the object was put into the molten pool. Most
easily worked metals melt below this temperature so it would only
work on things like iron and nickel with very high melting temps
they would have to be very clean and oxide free for the gold to bond
to the surface. I have heard of people referring to fire gilding as
dipping the piece in molten gold but fire gilding is a amalgamation
process where gold is mixed with mercury and the resulting paste is
applied to an object and the mercury is then driven off by heat.
The gold coating is then burnished down to smooth and polish the
surface.
Jim Binnion James Binnion Metal Arts Phone (360) 756-6550 Toll Free
(877) 408 7287 Fax (360) 756-2160 http://www.mokume-gane.com
@James_Binnion Member of the Better Business Bureau
Hi Have any of you tried, or heard of, gold plating a metal object by dipping it in molten gold then burnishing etc the surface?
Jack, This is unlikely to work because the liquid gold probably
won’t ``wet’’ any other metal (with the possible, but unlikely,
exceptions of copper and silver. It also seems a bit odd; it would
be cheaper and easier to electroplate the the gold. That said, I
haven’t tried it; if you do, I’d like to hear your results. dpm
Jack, I would think that the temperature of molten gold of any karat
would certainly destroy any organic object it comes in contact with.
Inorganic stuff like stones would shatter from thermal shock or
simply decompose. Most nonferrous metal would melt and tend to fuse
in to form an alloy. Copper, bronze, and some brass all melt about
the same temperature of pure gold. I would think only the ferrous
metals would survive the heat but surface oxidation would tend to
prevent any bonding. I am wondering if the description of molten
gold can be pushed to cover the process of vacuum deposition
(spelling)? At times like this I wish I had an engineering degree.
Bill
Please don’t forget to add that mercury vapors are extremely
dangerous and should not be attempted unless you have a sealed
blowout paneled box or at least enough sense to stand up wind
outside and that is not a good practice as what are you putting into
the atmosphere… best way for depletion guilding is to have a
condensing tube to allow the mercury to turn back into a liquid…
for that fact i don’t suggest mecury at all! Ringman
Please don’t forget to add that mercury vapors are extremely
dangerous and should not be attempted unless you have a sealed
blowout paneled box or at least enough sense to stand up wind
outside and that is not a good practice as what are you putting into
the atmosphere… best way for depletion guilding is to have a
condensing tube to allow the mercury to turn back into a liquid…
for that fact i don’t suggest mecury at all! Ringman
Hi Have any of you tried, or heard of, gold plating a metal object by dipping it in molten gold then burnishing etc the surface?
In gold, I’ve not heard of this. But it does vaguely resemble the
“wave soldering” technology used in electronics. In that method, a
circuit board can be held just above the surface of a molten
container of tin/lead solder, which of course melts MUCH lower than
golds, around 400 to 600 degrees F. A wave traveling across the
solder tank traverses the underside of the circuit board,
simultaneously soldering all the prepared connections. But I’m not
aware of anything like this being done in golds, perhaps simply
because the temperatures of molten gold alloys usually equal or
exceed the melting points of most of the things you might wish to
cover with gold.
However, I wonder if your term for “dip plating” has not been
misinterpreted. When I read that term, I normally associate it with
what’s often also called electroless plating. This is a type of
electroplating which does not use a direct source of voltage to cause
an electroplated layer. instead, the jewelry (or whatever) item to
be plated is connected to a wire of other “electrode” of a more
chemically reactive metal, such as zinc. This combination is then
dipped into a specialized type of gold plating solution. The
connection between the reactive electrode and the less reactive metal
to be plated sets up a weak galvanic cell, which generates enough
voltage to cause gold to be electroplated onto the surface of your
work item. It proceeds only until the surface has been covered
enough to be chemically and electrically isolated from the solution
by the built up gold, at which point chemical equilibrium is
reached, and the plating stops. For some items, made of already
reactive enough metals, even the wire isn’t needed, as the item
serves as it’s own electrode. The method thus produces very uniform
in thickness deposits, which are typically considerably thinner than
those produced by normal plating methods with an external power
supply. But the method does not have the problems with “throwing
power”, that in normal plating lead to thicker deposits on edges, and
less, or even no, plating in highly recessed or interior surfaces.
The deposits are generally intended for cosmetic advantages, where
long term durability is not needed. Often, these solutions are
directly marketed to the public, since it allows folks to renew the
gold plated look on their costume jewelry without needing anything
other than the solution and the specialized wire to hang the item
into the solution with. The basic operation of this method is about
the same as what occurs if you put your silver or gold jewelry item
in your pickle pot while it’s in contact with steel or iron. If the
pickle has been used for a while and has dissolved copper in it, then
with iron contacting your work, copper will plate out on your work.
The electroless gold plating solutions (also available to plate
other metals, including tin, for electronics use, or silver or
copper, I think, for various uses.) are a bit more costly than
comparable normal solutions made with the same gold concentrations,
in order to allow the deposits produced this way to be properly
adherent. Of course, as with any plating, the items have to be
properly cleaned first.
Hope that helps.
Peter Rowe