I have been interested in gold plating for some time but have
never taken the plunge on purchasing the equipment. I recently
brought up gold plated jewelry with a client who was very
interested in my making plated pieces. I would be plating sterling
silver. So here are my questions for Orchid:
My first suggestion is that you should let a professional do it for
you. Plating like any other skilled craft requires time to learn and
practice to keep those skills in place. Saying you want to do some
occasional plating to enhance the quality work you already do is
kind of like saying you want to do some occasional engraving on your
work if you don’t already know how to engrave. Yes you can do some
basic work with a little time and effort but it will not be top
quality work without a lot of time invested. A poorly done plating
job will definitely hurt your reputation with your clients because it
looks so bad.
What should I look for in gold plating equipment? If I go ahead an
make this equipment purchase I would be plating up to large cuff
bracelets, rings and necklace sections.
The basics are a couple of heated tanks and a power supply
(rectifier) and the cleaning, and plating solutions. And this is all
most folks who do their own plating have in the studio. If all you
want to do is make it yellow (or white depending) and have it last
till it gets out the door this is fine, however to do quality plating
you need a little more. You need precise control of the temperature
of the bath along with control and monitoring of the current and
voltage applied to the work, agitation of the solution (preferably
with a pump and filter), the ability to monitor bath chemistry,
plating thickness and a lot more knowledge than comes in the little
booklet from the jewelry supply along with the plating kit.
Plating baths are sensitive to contamination and the work must be
chemically clean of all dirt and oxides or the plating will not
adhere properly so the cleaning process must be strictly followed or
the plating can just peel right off almost immediately. You must
never allow the current going to the work or anode to be interrupted
during the process, if it is then you will have multiple layers of
plating not a single uniform layer. This also leads to poor lifetime
of the plating job.
To put a plating job on a piece of silver that will last and not
tarnish you need to first plate the silver with copper than follow
that with a bright nickel plating and finally the gold. If you just
plate the silver with gold the silver atoms will diffuse into the
gold fairly rapidly and the gold will loose its luster and begin to
tarnish. The copper provides a good foundation for the nickel and
the nickel acts as a diffusion barrier and the nickel when done right
provides a very bright shiny substrate for the gold plating.
How thick can the plating be done? and how is thickness obtained?
How much time is involved in the plating process and what is the
process in basic terms?
The current density (current/area of the object being plated - amps/
square inch) plays a tremendous role in the quality and thickness of
the plating. Thickness will depend on the metal being plated, the
bath chemistry, current density and time in the bath. The higher the
current the thicker the plating in a given period of time and the
worse the surface quality will be. So there is no simple answer to
how long it will take. But to do a copper, nickel, gold plating job
might be an hour or so in the baths depending on how thick you are
plating.
More than 2.5 microns of gold is legally considered heavy gold plate
or Vermeil by the FTC anything less than 0.175 microns is not
allowed to be called gold plating. You can put on a lot of metal but
it requires you to slow down the process (reduce the current density)
so that you get a even build up. When you do very heavy plating it is
called electro-forming.
Does plating cover heat scale on sterling or does it have to be
removed prior to plating? Is there a company in Orchid land who
does plating so that I wouldn't have to do it myself, a
subcontractor? Does a sub make business sense for a one man
operation?
Yes you can plate over firescale and it is one good way to hide it.
I use Red Sky Plating in Albuquerque and they have done good quality
work for me. I used to plate printed circuit boards for HP many
years ago so I have (or had anyway) a good working knowledge of doing
quality plating and there is no way I would do it in my shop. It
takes too much room and frankly the best gold baths are cyanide based
and I just don’t want the stuff around.
Does plating affect stones, should they be set before or after
plating? stones like turquoise up to diamond.
All most all the baths are either strong acids or bases and can
damage many stones. I certainly would not want to plate a piece w
turquoise in it but diamond is not going to be hurt but you have to
be certain that it is super clean behind the stone so that you done
screw up the plating in that area.
What type of ventilation is necessary for plating equipment?
Good ones, you are talking about hot acid plating solutions for
copper and nickel, hot alkaline cleaning baths and gold cyanide
baths. all of them make nasty fumes.
James Binnion
James Binnion Metal Arts