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Soldering with no holes to clean diamonds

Sorry about this boring subject, but got to make a living. Just
wondering if anyone has some way of soldering with diamonds in place,
Ihave a large round 18ct gold pendant which has the chain runner on
the backand it’s broken so I need to solder a new one on but the
diamonds are grainset and don’t have any holes at the back for
cleaning, if I heat it up and there is any dirt they will burn, so
has anyone got any suggestions besides taking out all the diamonds,
there are 75.01ct diamonds. This is becoming more and more of a
problem with imported jewellery so any advice would be appreciated


You can soak the piece overnite in caustic lye. It will remove all
of the organic substance. I usually use Red Devil brand that I buy at
the local hardware store. Mix a couple of table spoons in 8 ounces of
cold water and then I put it on a coffee cup warmer or hot plate to
heat up. If it is really filthy you can leave it in the lye a couple
of days. This will also work on gold chains that have a lot of hair
twisted in them. For closed back I usually soak overnite then ultra
sonic and then soak again. Closed backs take longer than ones with
holes but it works. Be sure and rinse well under hot water and then
to the ultrasonic and steamer before you torch. Frank Goss

Good luck finding Red Devil. In PA I am told nobody carries it
anymore because of the restrictions of Homeland Insecurity. It is a
major ingredient in producing drugs evidently.


Good luck finding Red Devil. In PA I am told nobody carries it
anymore because of the restrictions of Homeland Insecurity. It is
a major ingredient in producing drugs evidently. 

I don’t know about Red Devil, but sodium hydroxide is still in the
grocery stores here. You can even buy it from Amazon - in fact, they
have Red Devil for sale. If all else fails, probably Drano crystals
would work for this purpose. It’s about half lye.

Potassium hydroxide will probably work as well. It’s easy to make
that yourself. My father used to make it periodically for my mother
to make soap.

Al Balmer
Pine City, NY

Well, as for the cleaning first- definitely do it. as for lye- use
the loupe and check to see if it’s truly necessary to go beyond a
good cleaning in an ultrasonic then steam or whatever works to your
satisfaction. If you do see a lot of organic matter in the settings,
then acid bath sounds reasonable As you said any dirt may burn off if
you heat it from behind- but it certainly shouldn’t take the heat at
which 18 kt.

flows to burn off gunk. Anytime someone brings me a repair piece
that has stones I know has inclusions, I explain the hazards to them,
and if the piece is insured then no need for a waiver- if uninsured,
and I can see visible inclusions in crappy stones, then a waiver. I
don’t mind replacing a couple of rose cut round brilliant stones,
particularly if easily set, but if the person is not a regular and I
suspect problems, I deal with it as it seems most proper (and
sometimes sell them Jeweler’s Mutual insurance!)…in other words
cover all bases if you agree to do the work and are uncertain of your
skills.-or contract- it out to someone who can. Sounds like you’re
simply replacing a slide or a jump ring. shouldn’t blow up a diamond
if its clean and there is some thermal protection on the stones and
beads/grains to the extent possible.

Before soldering you could always put some thermal protective paste
on the front of the piece, or use one of those water cool cups sold
by vendors. It should be a very easy and fast solder job so the
grains shouldn’t melt down. If you are really worried about your
soldering skills, use a repair solder rather than a plumb solder. If
you do use a thermal protective paste (or paint each grain with
yellow ochre, etc.) you’ll have to re clean again, but most of the
dried bits of paste will come off with steam jets, then pickle if any
flux glass is on it then a swim in the ultrasonic…

(By the way Red Devil IS NOT sold any more due to meth-amphetamines
makers ruining one’s ability to buy many OTC items that are now
"restricted" -so any stock you may still see on shelves is leftover
from a freer era, So buy it if you need it (it’s great for so many
things),just don’t mention it’s being restricted to the cashier so
it’s not pulled- someone else may need it too !)…rer

Although I miss Red Devil, you can use any drain cleaner. We use the
liquid stuff. It works just fine.

Have fun and make lot s of jewelry.

Jo Haemer

When I started at the bench almost everything had a clean-out hole
behind the stones, which I thought was proper. Over the years I
started to see more and more diamond pieces with no holes. I did a
lot of complaining about what a problem this was going to be for the
poor saps that had to repair the stuff down the road! Just for the
reasons you say Simone.

To my surprise, it really has not been a problem as long as you clean
it well first. Usually I will just hang it in a running, hot sonic
for a few hours or if I’m really worried about getting it super clean
I’ll soak it in liquid drain cleaner for a hour (in a closed jar in a
basket in the hot sonic) or do both. Then just boric acid and alcohol
and solder as you would normally and it’s usually just fine.


The biggest issue we run into here with blind set (no holes) pieces
is not during soldering, but after polishing. If the piece is steamed
too quickly and the steam is aimed directly towards the stones
without being in the ultrasonic long enough, the compound can get
forced behind the stones, turning a two minute cleaning into a day
long ordeal.

After polishing, steam from the back first just like it had holes
and re-ultrasonic, repeat as necessary. Never aim the steam directly
at the stones until the piece is really clean, or you’ll likely wish
you hadn’t.

Dave Phelps

Who is sorry for his extended absence. I was grounded. Long story
involving an old car, Orchid and an ice storm.