Advice for soldering 20ga silver

I’m doing work for a designer who insists on using 20ga Sterling
Silver as the backing for all bezel mounts. Some of his pendants can
get pretty large at around 3 inches. I’m using a screen set up on
fire bricks and heat from beneath. I use boric acid and alcohol for
fire scale.

The problem is occasionally some sort of impurity makes its way in
the silver leaving a deep pit about .5 mm wide that won’t buff out.
I bought a new screen. My screen is now fully coated with melted
boric acid from subsequent soldering. I’ve also used a stiff wire
brush in-between soldering. Still occasionally I get an impurity.
I’ve tried supporting the piece on charcoal blocks but have problem
with the piece drooping when reaching solder temperature.

Thanks in advance for any advice.

Rick Copeland
Silversmith and Lapidary Artisan
Colorado Springs, Colorado
home.covad.net/~rcopeland/

Hi:

Try turning it so your bezels are under the plate…much easier for
the bezel to get to temperature than the plate before you fry the
bezel.

Ringman

Rick,

there’s nothing wrong with using 20ga sterling. I use it all the
time. You said you had a problem with soldering on a charcoal block,
What kind of problem did you have?

I only use charcoal, but I use the compressed German charcoal
blocks. they last alot longer than the cheaper ones and provide a
good support for the metal. I happen to like the conductivity of the
charcoal, it retains the heat from the bottom as you heat from the
top. I use mostly medium and IT solder on the block. But try to
keep the block free of borax. it tends to get sticky and the silver
gets sticky and then the charcoal starts to get all over your piece.
I have used ceramic surfaces to solder on and they are okay, but I
prefer the charcoal.

We all have our own methods we have developed over the years and it
is all about “what makes you comfortable” with what you are doing.

Please feel free to contact me regarding your problems with
soldering. I teach jewelry design and enamelling and I am more than
happy to help you figure out your problem.

Jennifer Harris Friedman
enamellist, jewelry artisan and holloware
Ventura, CA
jenenamel@sbcglobal.net

Rick,

You did not mention if you are using a flux. you did mention Boric
Acid and Alcohol as a coating to protect from fire scale.

Try this and see if it works for you.

First make sure your Boric Acid and Alcohol is not leaving too thick
of a coating after it is burned off. It should leave a white
powdery film and not a thick caked on layer.

Next try using a third hand with soldering tweezers. Hold the
corner of the twenty gauge sheet with the tweezers and lay the bezel
in place. Add flux along the edge of where the bezel meets the
backing only ( I like using Borax and water ). Add some small snips
of solder on the 20 gauge sheet along the inside of the bezel. I
would place a small snip every 2mm - 3mm apart.

Heat the 20 gauge sheet slowly from underneath in a circular motion
until the solder balls up and then starts to drop and flow, making
sure not to over heat the metal.

If you are having problems you should Pickle and clean the piece
before you do more work. Do not use a metal brush in between
soldering.

I think your wire brush or metal screen combined with over heating
the metal may be what is causing you the problem.

Good Luck
Greg DeMark
email: greg@demarkjewelry.com
Website: www.demarkjewelry.com

    I use boric acid and alcohol for fire scale. 

Also try coating the entire piece with Prip’s Flux after your boric
acid/alcohol firecoat. Fripp’s Fabulous Flux works as well. The
additional ingredients also turn glassy and add protection from
firescale.

  Add some small snips of solder on the 20 gauge sheet along the
inside of the bezel. I would place a small snip every 2mm - 3mm
apart. 

One thing I try to impress on my students is …less solder is
good!

If soldering a 22X30 +/- bezel, only 4 medium size snippets are
needed placed N-S-E-W…especially if the bottom of the bezel has
first been made flat on sandpaper and the plate is flat.

Larger bezels up to 30x40 +/- add two more snippets.

If using the very very small snippets (i.e., the prechipped stuff)
add a few more.

When too much solder is used, it fills the join and penetrates into
the metal, it fills the boundries around the metal grains but then
has no where else to go. So it builds up on the surface as a fillet
between the bezel wire and the backplate. If you use less solder,
the join will be neat, sharp and strong. If there is not quite
enough to run all along the length of the join, just add a snippet
or two.

Otherwise, I like they way Greg describes the process…I too use
the tweezer method…I call it ‘air soldering’. Be careful though
that you don’t overheat the metal…especially in the area near the
tweezers. If it gets too hot, it will sag and cause more problems.
I like to first heat the entire backplate but as it comes up to dull
red, I point the flame away from the tweezers and solder the outer
areas first. Then I lay it onto a soldering brick and quickly pick
it up again on the opposite side…and proceed as above. Takes
about 30 secs to solder a 22x30.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2

I have a Meco jeweler’s torch (which is sorta smallish) and have
totally abandoned using a tripod and screen for soldering (way, way
too much of a heat sink). Through a workshop that I took about 7
years ago, the teacher used a weighted 3rd hand tweezer holder to
hold the piece to be soldered. The 3rd hand joint allowed it to be
positioned at any angle and you could easily heat from underneath
(helpful if you use thin bezel cups on top or if the base is quite
thick). I have used this almost exclusively. When doing large or
heavy pieces, I make sure I have excess silver base on hand to
maintain the setting’s strength (in the case of an extended edge)
and on which to attach the tweezers. Once all soldering is done, I
trim this excess off. In the case of earring shapes that are
pre-cut with a blanking die (where there is no excess metal), I
sandpaper the holding tweezers between solderings to make sure they
are clean (otherwise, you will get ugly black marks on your metal).

Good luck!

Elizabeth
www.borntobeworn.com

Sorry I forgot to say you place your solder and heat till the flux
sticks the solder to the inside of the bezel sheet area. Then turn
over and finish.

Ringman

Hi Rick

I've tried supporting the piece on charcoal blocks but have
problem with the piece drooping when reaching solder temperature. 

Instead of suspending the piece on charcoal blocks and soldering
from underneath, place the entire piece on charcoal (or “magnesium”)
and solder from above. I spent years soldering large bezels to
sterling sheet before I started working with gold and I always
soldered from above. Leaving any part of sterling sheet unsupported
is just asking for it to slump because it is such a great conductor
of heat.

When soldering a large bezel from above, use a very large flame and
be sure to keep it away from the bezel itself. Heat around the
outside of the bezel as well as inside.

Both charcoal and magnesia blocks will help the process if you heat
them first, since they will reflect heat back to the silver. I
solder with the piece flat on the block but, in previous posts on
this subject, others have mentioned that placing the piece on a
screen which is then propped very slightly above the block’s surface
is even better. That way the heat from the block can more easily
reflect onto the bottom of the piece. If you try this, I would
suggest using a much lighter weight screen than the kind that comes
with the tripod setup so that it has less of a heat sink effect.

Hope this helps. Beth

Don,

I do agree with you that too much solder becomes a problem. I guess I
should have qualified the size of a snip of solder. I cut my own and
each is about 1 x 1mm.

Good luck
Greg DeMark
email: greg@demarkjewelry.com
Website: www.demarkjewelry.com

Rick

I like to rest the sheet on a little “squiggle” of binding wire.
This allows for better heat conductivity, but without too much of a
heat sink, often a problem with third hands and mesh set-ups.

Elizabeth

Thanks for all the on and off-line tips! It’s not a one size fits
all situation with each piece presenting it’s own unique challenges
but now I have a few more “tools” to approach each situation thanks
to the Orchid community.

Rick Copeland
Silversmith and Lapidary Artisan
Colorado Springs, Colorado
home.covad.net/~rcopeland/

Hi, Rick,

I’m catching up on my Orchid mail, so this may not still be needed,
but no one mentioned my methods.

First, read my post from 2000 about soldering from beneath using
titanium supports:

(the second part of the post). This has worked well for me for years.
I put my brick or charcoal block in the middle of an annealing pan so
I can turn it slowly while bouncing the heat up onto the bottom of
the piece. If you do it as I describe, it is impossible to melt your
bezel. If you like the idea, send me your address off-forum and I’ll
send you the titanium strips.

The other thing that always works well for me with a really outsized
backing, especially with a large but delicate bezel, is to put the
piece, ready to solder, on one of those little “trinket kilns” that
Rio and others sell, that look like a little frying pan made out of
fire brick. They are often used for granulation. They provide heat
from below-- enough to pretty nearly melt your silver if left too
long-- so a tiny bit more from above with a torch will melt the
solder and draw it around the bezel. The heat is even enough to
avoid warping.

HTH!
Noel

Noel,

I always appreciate your postings so generously provided.

As you have volunteered, I would like to try your titanium supports
for soldering bezels to large sterling silver backings… with
the heat source to the underside of the silver backing plate. Also,
what is your favorite heat source? Acetylene only? With oxygen?
What number flame tip?

Happy to reimburse you for materials and postage, if you would
kindly advise.

Thanks much.
Paul
Paul Hartstein
4210 California Ave.,
Long Beach, CA 90807
@Paul_Hartstein1

I’m just catching up on back Orchids and found this thread. I
believe soldering small objects on sheet should generally be done
from below. To prevent sagging, I solder on quite fine stainless
steel mesh. It works well for small things—about a 3 1/2" square.
It gives a perfectly flat surface while at the same time allowing
the flame to be/go underneath. I cut the size I want and fold over
the edges for a sort of self-frame for support. Could probably use
the fine mesh for large sizes as well so lonf as you give it a firm
frame. You can put it on a tripod, between blocks, or hold it with
tweezers. I often put it flat on on the soldering block and lift the
mesh from a corner with a soldering pick or soldering tweezers. This
allows me to put it down flat momentarily if I want to gently press
something into place, etc. on a hard surface or go back and forth
between heating from above AND below. When using a tripod and
soldering from below, I hold a large soldering slab above the piece
but as close as possible to it to reflect the heat back down on the
piece. It’s in effect heating from both above and from below at the
same time, without having to turn the piece upside-down.

Janet in Jerusalem

As you have volunteered, I would like to try your titanium supports
for soldering bezels to large sterling silver backings.........
with the heat source to the underside of the silver backing plate.
Also, what is your favorite heat source? Acetylene only? With
oxygen? What number flame tip? 

OK, I am saving the addresses of the people who have asked, and will
send out another round of titanium strips. Don’t worry, the cost is
not worth reimbursing. I’ll send strips to the first 15-20 who ask,
if it goes that high.

I’m not really fussy about the torch. I have an acet/air Smith that
I used happily for years, and also use both places I teach. I also
have a Meco Midget propane/oxy which I bought because the acet/air
wasn’t good for fusing. Now, I pretty much use the latter, as it is
more versatile, and it is really nice, for the occasional large
project, to have two torches available.

Tip size depends entirely on the size of the project, but this does
bring up one relevant point-- when you solder from beneath,
especially when bouncing the heat off the brick, block or pad and
back up onto the piece as I do with the help of the ti V’s, you must
use a much larger flame than you would for more direct heating.

This technique is not really different from using a “nest” of
binding wire or a pile of nails, as others have suggested, except
that it is perhaps more elegant. The small titanium strips last
indefinately, don’t act as a heat sink, are not messy, and offer
good, level, even support. You get most of the same benefits making
your V’s out of copper, except that with ti, it is literally
impossible to solder them onto your piece by accident.

I’ll give it a couple more days, then gather up the requests and cut
some strips of ti.

–Noel

I would like to try titanium supports. I have a hard time with bezels
for larger stones.

Carolyn Duncan
2637 G ST
La Verne, Ca
91750

Orchidians,

Noel is doing a real mitzvah here:

 OK, I am saving the addresses of the people who have asked, and
will send out another round of titanium strips. Don't worry, the
cost is not worth reimbursing. I'll send strips to the first 15-20
who ask, if it goes that high.

I got some of the Ti strips and made some "V"s. They are pretty
nifty.

Here’s another use: I punched/cut a tiny little “mouse hole” in the
edge of one leg of the “V”. That little opening is just big enough to
fit over chain and acts as a flame shield when soldering chain ends.
As Noel says, copper strips would also work, but the Ti “V” is more
durable and doesn’t solder to your work.

Thanks Noel, Judy in Kansas

Judy M. Willingham, R.S.
B.A.E. 147 Seaton Hall
Kansas State University
Manhatttan KS 66506
(785) 532-2936 FAX (785) 532-6944

Hi Paul,

I would like to try your titanium supports for soldering bezels to
large sterling silver backings.. 

I haven’t been following this discussion, but depending on the size
of titanium you want/need, you may be able to find some locally. If
the stuff is wire size, stop in a bicycle shop that does repair
work. Many times they’ll have titanium bicycle spokes that have been
damaged that you can get free or at a very good price.

Dave

I prefer oxyacetylene as it’s heat range is much faster and higher.,
Ringman