Tip for Soldering Pin Backs

Does anyone have any tips for soldering sterling silver pin backs? I
invariably have to try several times before I accomplish it. Half
the time I solder the clasp closed; the other half the flux is
exhausted before I get it done. If I do(purely by chance!) get the
clasp soldered, more than likely it has moved slightly from where I
wanted it. I am using the clasps and hinges from Rio. I was told
that someone else makes a larger silver hinge. Does anyone have a
source? Absolutelly any advice would helpful at this point!20 J.C.
Thomas

I assume that you are referring to the small silver safety clasps
that Rio sells. I have found that if I coat the moving parts of the
clasp with white-out, it keeps the solder from running onto the moving
parts. I cover the piece with flux and I place the clasp on the piece
and put a small ball of medium or easy solder at the seam. I heat the
entire piece and when the ball of solder looks like it is getting
ready to flow, I place the flame on the other side of the clasp to
draw the solder through. The tricky part is removing the white-out
when I’m through. Sometimes it will come off in the pickle, other
times I have to brush it or put it in the ultrasonic. I hope this
helps! --Vicki Embrey

Hi, JC-

I am assuming that you are working in silver. The challenge in
soldering pin backs and similar things is the fact that solder tends
to flow towards the heat. The pin back, being small, will heat up
faster than the piece itself, causing the solder to flow up onto the
pin back. Concentrate on bringing the piece itself up to soldering
temperature, the pin back will get plenty hot just from conduction.
You can try placing the piece to be soldered on a tripod, and heating
from beneath to bring everything up to soldering temperature. You can
also minimize problems by using a lower temp solder (easy or even
easy-easy.) You can melt the solder onto the piece first, quench,
pickle, and then place the pin back and reheat until the solder melts.
To prevent the pin back from shifting position when soldering, you can
use a third hand (tweezers on a stand, available for less than 10$
from most jewelers suppliers) to hold the pin back while you solder.

Also, before soldering, make sure your piece is immaculately clean.
Solder won’t flow on a surface which is oxidized. You might try using
emery paper on the place where you are soldering the pin back, just
to make sure it is clean and ready to receive the solder.

Soldering takes practice and a “feel” for what you are doing. Don’t
be discouraged- nobody gets good at soldering without having a few
misadventures along the way.

Hope this helps-

Lee Einer

Hello J.C. Thomas,

Does anyone have any tips for soldering sterling silver pin backs? I
invariably have to try several times before I accomplish it. Half the
time I solder the clasp closed; the other half the flux is exhausted
before I get it done. If I do(purely by chance!) get the clasp
soldered, more than likely it has moved slightly from where I wanted
it. I am using the clasps and hinges from Rio. I have had success
with soldering the Rio catches (without soldering them closed) by
doing two things before soldering: 1. File the base to be sure it is
clean for the solder to flow and then apply Battern’s Flux ONLY to
that filed base 2. Use White-Out (or other flux inhibitor) to coat
the rest of the catch It goes without saying, that you will use Prip’s
flux to control fire scale before putting torch to the pin. Also
solder the catch in the open position.

Another good practice is to sweat solder the catch base.  After the

steps described above, you can hold the catch upside down with
soldering tweezers or press it into your soldering block. Heat the
solder just 'til it flows on the base, then place the catch where you
want it on the pin, and heat the pin until the solder flows. (You may
need to lightly file a flat spot on the solder so the catch will sit
upright on the pin.) Again, be sure the spot on the pin is clean and
properly fluxed before sweat soldering. A quick solder enables you
to limit your heat. Best of luck, Judy in Kansas where I just finished
a 2-day outdoor show in 100 degree heat… on pavement, no less!

Judy M. Willingham, R.S.
Extension Associate
221 Call Hall Kansas State Univerisity
Manhattan KS 66506
(785) 532-1213 FAX (785) 532-5681

Make sure the joint and catch are flat on the bottoms by sanding
them. Use sandpaper (320 or 400 grit) on top of a piece of window
glass, rub the catch and joint in a circular motion on the sandpaper.
Rinse them to remove the residue.

Use water-based correction fluid or ochre to coat the catch
mechanism. Make sure you get it inside the little wheel part. This
will prevent solder from wicking up the catch and freezing it. Dry the
coating well with a soft flame. Make sure there is no residue on the
bottom of the catch.

Coat your main piece with a fire scale inhibitor and dry it with a
soft flame. Add a little flux where your catch and joint will be
placed. Dry it with a soft flame enough so it is no longer bubbly but
has not yet gone to the liquid stage. The flux should be fairly flat,
but still white.

Put on a small chip of solder on top of your fluxed areas. Bring your
piece up to heat just long enough for the solder to slump, but not
flow. You want to wind up with a little bump or pimple of solder.

Now set your catch part up in the self-locking tweezers. Run your
flame around the solder on the one end you want to attach the catch
part, while at the same time holding the catch in the flame to
pre-heat it. When the solder flows, drop the catch down into the
molten solder with a fluid motion. Bring the flame up to concentrate
it on the catch, but keep it moving so you don’t overheat the catch.
As soon as you see the join completed, blow on the catch to cool it.
One quick, strong puff will do it. Now do the same for the joint
part.

There is no substitute for experience. Practice with a couple of
little pieces of copper about 1" x 2" and some of the cheap pin sets.
Practice with the joints first, doing 10 of them. Another piece of
copper and practice putting on 10 catches. Another piece of copper,
and practice putting on both sides of the set so you can control your
flame without flowing the solder on the other pieces and upsetting
them. A couple of dollars and a few hours will be all you have to put
out to become expert at it.

Hope it helps. K.P. in WY

Hello, On the question of soldering pin backs. This is a place I like
to use paste solder. You need to be careful not to add too much. If
you do the parts can move when the flux dries. Put the piece on a
screen with the pin parts up. Heat from the under side. You can
solder without heating the pin parts at all. On larger pieces or
with smaller torches, you may want to heat very well from the
underside (seeing dull red on silver) then swing the torch to the top
to get the solder to flow. Do not heat just the pin parts or the
solder will flow to the top and solder them closed. Steve Ramsdell

Thomas,

WIth pin backs - practice makes perfect! First I apply yellow ocher
to the catch mechanism. Then I apply soldier to the backs of both the
joint and catch. A bit of gentle heat to the back of the pin and
touch the joint or catch down when the temperature is right. This was
a frustrating thing for me to do for some time, but it gets easier
after the first few dozen.

To prevent swiveling I put a steel pin through the joint or catch and
hold the pin with my tweezers, this gets the tools out of the way of
the flame so I can see and I can hold the item in place a second while
the soldier cools. I also use a center punch to make a dimple where
the joint or clutch will be if it will not show on the front of the
finished piece.

Good luck -

L.J. Smole
White Fox Workshop
Ozark Mountains, USA

Dear Judy,

To solder a safety clasp takes a bit of practice. It is important to
position the closing mechanism in the “nuetral” position, that is, w/
the tabs or “ears” in the Mickey Mouse ears position (both tabs at the
top), neither open or closed. This positions the mechanism as far
away from the solder as possible. I place the catch in a pair of
cross lock tweezers and freehand solder it to the piece, but you can
also place the tweezers in a third hand. Melt a small chip of solder
on the brooch itself exactly where you want the catch to be (w/out the
catch in place). The idea is to reflow the solder w/ the catch
resting on that solder nub. DO NOT FLUX THE CATCH!!! There will be
enough flux on the brooch and its solder to lube up the very bottom of
the catch. W/out all that lfux on the catch itself, solder is very
unlikely to run up into it and gum up the works. Be sure to heat the
brooch and not the catch. The tweezers are a heatsink that keep the
catch from heating up too much and thus drawing solder to it.
Another thing to try is a nickel catch, which doesn’t suck up solder
like a sterling one and is actually stronger than sterling. Good
luck, Andy Cooperman

1 Like

Hi J.C. - I also use the pin catches and joints from Rio Grande. And,
I too was having A LOT of difficulty with catches soldered shut,
joints moving, etc. But, it was an absolute requirement that I be able
to solder pin backs - my production line is mainly pins! After many
foiled attempts, I’ve got it down to where I rarely have any more
problems.

Try these hints:

  • Heat the sterling piece slightly (before it gets to the pale tea
    color) and then dip into an anti-firescale/flux solution (I am
    currently using Magic Flame). Continue to heat the piece until you get
    a nice covering of the flux without getting a puffy, white, sticky
    mess (I think this has to do with the amount of water you combine with
    the Magic Flame).

  • Cut your small pallions (and I mean small) of solder and place them
    where the pin catch and joint will be. NOTE: I turn my piece upside
    down when soldering pin backs so the joint will be on the left,
    horizontal; and the catch will be facing away from me on the right
    hand side of the piece, vertical.

  • I then use tweezers to hold the joint while I heat the piece to
    flow the solder on the left hand side and when it flows, I place the
    joint, let go of the piece with the tweezers, and pull the flame away
    (DO NOT use fiber grip, cross-lock tweezers to hold either the catch
    or joint. They crush the catch when it gets heated and will ruin the
    mechanism)

  • Then finish heating the piece to flow the solder for the catch and
    place the catch in the same manner (I found that soldering the joint
    first worked best, since the whole piece could be heated and I
    wouldn’t overheat it and flow solder into the catch by accident).

It takes some practice but it works like a dream!

  • Lori Bugaj
    One-Eyed Collie Jewelry Design

Hi Lori,

I have never heard of Magic Flame. Can you tell me more about it and
where you purchase this item. Thanks Beth Katz

Hi Beth- To respond to your question Re: “Magic Flame”. I get it from
Rio Grande and it is basically a flux/soldering paste product that
they say can be used 4 different ways: as a fire coat dip (used with
denatured alcohol - I tried this and the smell was too gross), as a
flux, paste (each mixed with water - this is how I use it), and used
full strength as a casting flux. I am very happy with the results. I
mix it in a wide-mouthed glass jelly jar with enough water to make a
thicker, yet liquid mixture. I heat my silver piece slightly (before
it becomes the color of tea) and then with fiber grip/cross locking
tweezers, dip it in the Magic Flame mixture. Then you heat the silver
piece on your soldering block to give it a good all-over coating.

  • Lori Sorry it took sooooo long to respond - we finally got
    possession of our “new” 1889 home in San Francisco, and needless to
    say, I have been preoccupied with filling holiday orders and doing
    some quick home renovations so we can move in.