Silver Paste Soldering Problems

I find paste solder difficult to use on larger objects, so I can’t
help you there, but I do know a trick for soldering together two
halves of an enclosed item. One of my professors at school taught me
to do this and the first time I saw it I thought it was pretty much
the coolest thing ever.

As long as you are not planning on reheating the piece, you
generally can get away without an air hole. Just make sure you let it
COMPLETELY air cool before you throw it in the pickle, and keep your
pickle set on low so that it doesn’t get too hot.

To solder two halves together, first sand them so that they go
together with a very good physical connection. I find this is the
most irritating and slow part of the process, but it saves a lot of
time. Making a tape “handle” can ease hand cramping.

Take some wire solder and hammer it flat (or roll it through your
rolling mill if you are lucky enough to have one). Cut a piece about
5-8mm longer than needed to go across the piece. If the peice is
larger than an inch or so in diameter, don’t go straight across the
middle. so if I had a 50mm dome, I’d probably cut 4 20mm peices.

Flux everything. Place the bottom half on a trivet, then place the
solder strips across the piece with a little hanging over the edges.
Place the top half on top. This makes a little sandwitch of the piece
and solder.

Heat the peice evenly on the top and bottom. As it gets near
soldering temperature, make sure the seam is heated evenly. If
everything goes according to plan, the solder will flow, the top
piece will fall onto the bottom, and everything will be soldered
nicely. Let the piece air cool before pickling.

It takes a little practice, but has worked well for me. Hope it


Hi Beth,

Thanks for the good advice. I recommended the nick as I once had
something blow like a bottle rocket when it shouldn’t have. Luckily
it was small and it missed me, but it certainly did put the fear of
god into me. Quite spectacular. I never had any incidents before
that, but its nicks for me ever since. I do use yellow ochre on
occasion, but only because I am slow on the uptake. I will now be
looking for anti-flux. Who knew?..Oh yeah…everyone but me. Lol!


Lisa, (Went out dancing until 2am with my buddies for my birthday
Saturday, and then spent all Sunday dancing intertribals with other
pals at a pow wow here. Guess I am not as old as I thought…)
Topanga, CA USA

Thank you very much for your I have never used "stop
flow"and it is not listed by my usual supplier, however I am sure
that here in the UK I will be able to find it, thank you again.


As you have indicated in your post on Orchid, you and I will be
meeting in late August when I will be at William Holland School of
Lapidary Arts in Georgia for a week long class presented by Florida
Society of Goldsmiths (FSG). William Holland is where you originally
purchased the solder products from Unique Solutions. You never had a
demonstration of the products!

There is sometimes a learning curve for all products. Paste solder
is no different. I am hoping you read my lengthy post on how to bring
your metals to temperature BEFORE applying the torch flame to the
solder itself. As I mentioned before, it is important that all of
your project, as is the case with silver, be brought to the proper
heat stage just before solder flow and then gently coaxing the flame
near the solder and THEN after you are seeing some activity you can
go directly on top of the solder… NOT BEFORE. If you are getting
black crusty formations, you are overheating directly on the solder
and dissipating the flux that is built into the solder paste. Please
go to the archives and read the “how to” explanation and
troubleshooting suggestions that were sent to Brian on this list.

It would be my pleasure to show you, in living color, using the
paste that you bought from me two years ago; that there is nothing
wrong with the paste and that it will flow successfully and will join
the two pieces of metal. If the metal is not prepared properly, or is
not clean, this will also contribute to human error and may
contribute to soldering problems.

Please bring whatever piece or pieces you want me to see. I will
make sure it is prepared properly and will demonstrate using the two
year old paste solder. I will also have some of my own metal and can
use that as well. There must be some problem that is occurring in the
soldering process when you are trying to get the two pieces together.
Without actually seeing what is happening, I have tried my best, with
your description of the problem to diagnose what is happening and why
you are having problems with the paste solder. I stand behind my

I look forward to seeing you again. I will be at William Holland
when classes will begin on Monday the 28th and end early afternoon of
September 1, 2006. My only request is that you do not plan on seeing
me during class time; that will disrupt the classes and I will have
no opportunity to give you my full attention. So… either lunch time
or after class at 5 PM will be dandy. If you have a day in mind,
please let me know so I can expect you and that I will make
arrangements to have full access to the classroom torches. If you
wish to check out the wonderful classes being offered by FSG during
this week, please check the web site If anyone in the
Young Harris, Georgia area wants to stop by the William Holland
campus, please let me know and I will make arrangements to meet you.
Since FSG is a 501(c) 3 corporation, we always have an auction to
benefit the organization while at William Holland. I will have the
date and time posted on Orchid so those of you who want an
opportunity to bid on the goodies can attend.

Beth Katz
Unique Solutions, Inc.
Paste Solder and Powder Solder for Jewelers and Metalsmiths

The product that Beth Katz mentioned is probably as good as it
gets;however, if you don’t have any, you might try what I use. To
stop solder from flowing out from under a bezel cup, when necessary,
I usually just use a “Sharpie” marker. If I need to cover a larger
area, I just take a small brush and dip the tip into alcohol and then
swip it across my red rouge several times to coat the brush tip and
paint away.Just remember to clean it off the silver before dropping
into the pickle pot or it will coat the object with a very light
copper coating which will polish off easy enough,but prior cleaning
will prevent it.I also keep a very fine cheese grater on my bench for
grating the red rouge and making myself a little batch to mix with
alcohol, makes a creamy paste.Also, in regard to paste solder, I use
a small hair dryer on low to soften the paste solder.As soon as my
supply is gone, I won’t have the problem, I will order from Beth
Katz,hers has a proven track record for quality and long shelf
life.Usual disclaimers, :slight_smile:

best wishes, John Barton