Before becoming a jeweler, I did serious plating work as a graduate
student at a microfabrication lab, so I know a thing or two about
doing thick plating.
Here is the problem: rhodium done in most shop setups is not
conducive to lasting all that long. Even done under ideal
conditions, benchtop setups can really only provide a plating that
lasts about 6 months to a year with normal use. That doesn't account
for abuse, chemicals and body chemistry of the wearer. This is
really only talking about white gold alloys that are already setup
to kind of mask the fact that the plate is wearing through.
Palladium white wont show for quite some time and nickel white can
show up rather quickly depending on the other alloys in the metal.
Plating on top of yellow gold presents an even bigger challenge
since when it wears in one spot, it is really noticeable.
Standard plating done in the shop is measured in a handful of
microns. What you are asking for is something 10 microns thick or
greater to stand up to serious wear and that is near impossible to
do in the shop. You would need an expensive rectifier that can
provide both constant current or voltage, a plating solution far
more concentrated than you can normally get (most are around 5
grams, you would need something closer to 20) and a cage anode. If
you try it in your setup, going for something that thick will
either, burn, dull or flake. For the expense, it really is not worth
If you are determined to plate yellow gold, then i suggest this link
This is a great resource for electroplating Just browse
the forums and related links and it will give you plenty of insight.
Good luck my friend!