Speaking of lockets

Every so often a project comes across the bench here requiring
(like Lynn’s locket) the soldering of sterling charms. The big
problem that arises is when these are finished goods with a nice
nickel-and-rhodium plating to keep them shiny. I’ve never yet
found a good way to strip them (except, of course, polishing
them to death) to avoid that horrendous burnt-bubble grey mess
that results after heating them. Even polishing AFTER the
heating is not always as successful as my persnickety self
desires 'cause sometimes they are fairly pocked with little
details that just go to hell after all the abuse. Anyone out
there ever find a better way to rid sterling of plating
sufficiently to avoid the mess that results after soldering?

Kathy, stripped of all desire to solder more…

Kathy, At this trade shop I worked at years ago , we would
solder silver charms that were nickel plated using lead "soft"
solder. Just a little on the jump ring and it would hold fine
but it wouldn’t mess the finish up. Lead solder is a dirty word
to alot of trades people but it serves the purpose. Kathy E.

  Anyone out there ever find a better way to rid sterling of
plating sufficiently to avoid the mess that results after
soldering? 

there isn’t, really. But sometimes you can call the
manufacturer of an item, if you can identify them, and order
another one without the plating. Most commonly, though, Rhodium
plating is a great reason to go to the use of tix or stay-brite
solder… Cool enough that the plating isn’t harmed.

Peter Rowe

Hello Kathy, yes, there is a very easy way to clean up silver and
gold without any kind of chemicals after soldering.It requires a
special machine called a magnetic Pin Tumbler. What this machine
does… using rotating magnets …is the following .In a small
supplied container…with water and soap… and about 1/2 a
pound of TINY stainless pins. the magnetic machine causes the
solution with the pins to rotate at 2500 revolutions per
minute… the pins go into every nook and crany and completely
brighten evry surface. This works on gold, silver and bronze .

i have been using these machines for many years as a precursor
to polishing… allowing me to get the inside of complex pieces
nice and bright were normally the sun won’t even shine!!!

I have a few friends who own jewelry stores who have bought the
smaller versions because of the tremendous time savings that they
have seen in jewelry repair… it takes between 5 -10 minutes to
get a perfectly cleaned piece. these machines are available for
between $500- $1000. from a number of different jewelry
suppliers.

I hope this helps!!!
Dan
http://www.racecarjewelry.com

I’ve often wondered about a better way to get rid of rhodium
plating, too. If the plating isn’t too thick, I will gently heat
the piece (first making sure there is no lead solder of course)
until an oxide layer forms, let it cool, pickle, and repeat until
the silver comes through. Usually once or twice will do it.
Sometimes, though, the silver is plated with copper and then
rhodium, and this is much harder to remove. I’ve wondered if one
could use an electroplating outfit to strip the rhodium off, and
if it would leave a smooth surface, but I don’t have an
electroplating outfit, so I haven’t tried it. Any ideas?
Elizabeth

Hi there Elizabeth! Electrostripping doesn’t work on rhodium,
much to my dismay (you see, my employer just bought me a
beeyooteeful plating/stripping set-up! First thing I checked!).
It’s polish, polish, polish for me, I suppose, as the boss turns
white and shakes at the mention of tix or lead solder.
Fortunately, the number and frequency of plated silver bits is
not enough to cause a headache, it’s just that at this time of
year I’m already without fingerprints and any polishing I can
avoid allows me to retain my ability to pick things up and KEEP a
grip on them!

P.S. - Thanks Peter - and the other folkses - all info is
appreciated!

Kathy,

You shouldn’t even need to get the charm itself warm, just the
jump ring. Wrap the charm in wet paper towels then clamp a pair
of cross lock tweezers on it, isolating the jump ring w/ the seam
facing up, as far as poss. from the tweezers. The tweezers and
the towels will heat sink the charm and using a "hot, hissy"
flame (providing you have oxy/something), you can silver solder
the seam. Don’t pickle it as pickle will react to rhodium or
nickel. Just soak it in hot H20 and the flux dizzolves.

Andy Cooperman

   Hello Kathy, yes, there is a very easy way to clean up
silver and gold without any kind of chemicals after
soldering.It requires a special machine called a magnetic Pin
Tumbler. 

Yep. Great machines. but they won’d do diddly squat (technical
term :-)) to help the bubbled up mess that rhodium plating on
sterling becomes when you heat it to solder on it. They may be
able to reach all the surfaces, but don’t have the impact power
to actually do anything to that rhodium, which is, in addition to
being bubbled up, still as hard as ever. tumbling in a
convetional tumbler with steel shot will burnish the bubbles down
a bit flatter, but it will still look like crap ('nuther
technical term). A full tumble finish sequence, starting with at
least medium grit abrasive media might take it off again, but
wow. What a messy sequence and a lot of work to salvage a ten
dollar piece of junk silver jewelry… Easier to replace the
darn thing. And even if you do manage to get off all the
rhodium, chances are the customer will complain that the silver
now looks too white, or will be back in two weeks complaining
that the thing tarnishes now…

One perhaps useful bit of info, though. If you really must
remove bubbled up rhodium plating, the aluminum oxide graded
buffing compounds for platinum, such as sold by Gesswein, are
hard enough to actually remove the rhodium. the 700 platinum
tripoli will actually do the job. maybe not all that well,
since as the rhodium comes off, it’s harder surface resists
buffing while already exposed silver does not, so you end up with
an uneven surface that you’ll then have to buff even more to
clean up, and by then you’ve lost significant thickness…

But anyway, compared to the ineffective action of conventional
buffing compounds, the platinum compounds are clearly the way to
go if you have to remove this sort of heavy rhodium plating.
Bubbled up or not.

Peter Rowe

You are absolutely correct … a magnetic tumbler will not remove
the rhodium at all… I meant it does a wonderful job on silver
and gold.

when i have needed to remove rhodium, i have used a 3x superfine
3M fiberwheel mounted on my 2xGuesswein 55,000 rpm
handpiece…this removes the Rhodium very quickly and leaves a
surface that polishes with a kiss of the wheel and a touch of
compound. I use a larger version of this (slightly harder )for
degating my castings…in volume. the wheels last and can
immediately go into plastic media for prefinnishing. Best wishes
for Chrismas and the New Year. Dan http://www.racecarjewelry.com