Rehardening clasp tongue

I can not find in any of my books any tips or directions on how
to harden the tongue of a box clasp after it has become annealed
during soldering. I use 18k hard sheet. I have tried
work-hardening by gently hammering, by polishing, by burnishing,
by air cooling slowly. Nothing makes the metal strong enough to
hold its shape so that it fits the clasp structure with a good
click. It seems like such a simple thing but I haven’t found the
answer. Any suggestions? jars

Have you tried to tubmble it in a mass finisher with steel shot?
Sometimes this will give it just enough work hardening to do the
trick. Amy Peters

Hi Jars, When working in 18 kt the best solution is to make the
tongue for a box clasp out of 18kt nickel white gold. The nickel
in the alloy makes it a very springy 18 kt gold. Try not to use
18 kt yelow, green or pladium white gold they tend not to have
ability to become springy enough.

Good Luck,
Etienne Perret
Designing Colored Diamond Jewels
< >
20 Main St
Camden, Maine
USA 04843

Jars, We sometimes use an Exacto blade between the tongue and the
lightly tap the tongue on a steel block to temper it. Also a
little trick, although not for purists, it makes customers happy:
stretch a small piece of rubber band between the tongue, pull
one side taut and then cut it-it snaps back and stays inside the
tongue. Do the same with the other side. Make sure to use a
light colored rubberband and be sure it’s tucked inside the
tongue so the clasp operates properly.
Hope this helps. Bob Staley- B.Staley,Goldsmiths

Hey Jars, I have a small piece of slanted steel cut to fit inside
most clasps. You could use a butter knife. I insert it & hammer
on top of the clasp with a steel hammer while laying the clasp
on a steel anvil. Afterwards I upset (hammering with a steel
hammer) all the outside edges of the clasp. Some of my older
students have shown me the rubber band trick, but it’s only a
temporary step. Tightly stretch a heavy rubber band inside the
nose of the clasp then clip it off on either side of the clasp.
Hope this helps, Happy Holidays,

Jars, I work on tennis bracelets all the time worked on three
today.I never quench the bracelets after soldering or working on
them.I air cool them as quenching will take out the spring.I
have tapped them with a little brass hammer but it is not as
effective as not losing the tension in the first place.Also
direct your heat away from the tongue unless you are soldering a
break in the tongue itself wich I have occaisionally done out of
necessity.But most of the time I will just replace the tongue
rather than solder it as it will end up breaking again at some
point.You can heat sink the tongue by holding it in tweezers
while you solder it in place and use a small flame that is
directed in the area you are soldering.Get in and get out don,t
linger with the heat.If your solder won’t flow.Start over after
cleaning it. Regards Burned out after a long long day at the
mall in Colorado
Merry X-ma$$ J Morley Coyote Ridge Studio

A tricky thing to resnap a tongue.

Many jewelers believe that it is the very end of the tongue that
provides the snap, but if you do that then it will break at the
end of the tongue eventually, as any repair jeweler can attest.
If you bend a piece of metal back and forth on the exact same
spot it will break, particularly our metals with their poor
mechanical characteristics.

Instead one has to spread the stress, place it elsewhere in the
tongue, back from the end point.

Place a pair of half round forming pliers crosswise on the
tongue, several millimeters back from the end. The round surface
is on the top of the tongue and the flat surface supports the
bottom of the tongue. Grip securely with the pliers and slide a
knife blade (which has a wedge shaped cross section) towards
end of the tongue, towards the pliers, which lie across the
tongue (at 90 degrees to it). This sliding forwards of the knife
blade bends the tongue upwards, but not right at the end,
instead some millimeters back from it. Now the tongue will snap
beautifully and loudly into the catch and the tongue will not
break at the end because the stresses have been displaced
the end into the body of the tongue. This will snap much longer
than a tradtionally sprung tongue, will last a long time and can
easily be resprung but the goldsmith in the same way just


Charles Lewton-Brain/Brain Press
Box 1624, Ste M, Calgary, Alberta, T2P 2L7, Canada
Tel: 403-263-3955 Fax: 403-283-9053 Email:

Metals info download web site:
Book and Video descriptions:
Gallery page at:

If the tongue is stable where it bends ( i.e. , if it is not too
thin ) gently heat it and then quench it . Do not attempt this
if there are any stones near the catch !


I’m assuming from you saying that you use 18k hard it is the
refiners most brittle metal they supply. There are special
alloys used in clasps to maintain their tension. If not try
this, hammer with the wedge end of a jewelers hammer on the
tongue in the direction of its travel into the female end of the
clasp. Light hammering may not necessarily be enough, through
many repetitions this will harden any metal. If you are making
the clasp choose a heavier gauge metal and do not spread the
tongue to far. Air cooling slowly as you have stated only makes
the metal softer. Polishing or burnishing will do nothing. It
takes experimentation and experience to make it work time after
time. When I am working on worn out clasps I take a wide rubber
band and stretch it, sliding it as far into the tongue as I can,
clip off the edge of the rubber band so its not visible . I
don’t recommend this if your making it but it works well in
certain repair applications. make sure you do not make the
female end too wide because no matter how much tension you
create the tongue will not maintain tension if its forced to be
too wide open. I hope this helps Regards from PA Richard Schneider


Charles’s method of adding spring and spreading the tension by
lifting the back of the tongue is the same approach I would use.
I would like to add a couple of tips when making the tongue and
a handy solution to a loose tongue (not to be confused with
loose lips).

Tips: Do not score, file or crease the metal before folding, if
you are making your own tongue; never hammer on the fold itself;
and do not file on the fold either. All of those weaken the
metal. When finished, and after polishing, use a highly polished
burnisher on all surfaces of the tongue as well as on the inside
of the slot it slides into.

Solution: Here is something I discovered recently. Many times, a
clasp is loose because the tongue is too short. The problem is
that the back of the tongue is too far from the inside of the
place it snaps into, after it is inserted. If you can follow
that, then you will see that bringing the back of the tongue
farther back, will solve the problem. Do this in a similar
manner described by Charles: grab the very last mm or 2 of the
tongue with a pair of flat pliers, held in alignment with the
tongue (not crosswise). Hold the pliers so tight that they
cannot possibly slip. Stabilize the rest of the tongue by
pushing it against a piece of wood or metal and lift, making a
curl at the front of the pliers. This moves the top of the
tongue back, which takes up the slack (hopefully all of it)
which caused the problem. You might complain that the curl is
not aesthetic, and maybe it isn’t. But I feel that the function
of the clasp and its security is more important than an extra
curve on a piece of cleanly formed and polished metal that is
hidden 99.9% of the time.

It works for me, and I hope for you too!

Revere Academy of Jewelry Arts
760 Market Street . Suite 900
San Francisco . California . 94102 . USA
tel: 415 . 391 . 4179
fax: 415 . 391 . 7570
web site: http://www.

Hi Jars, What I do is quench it in water when its hot.(White gold
gets hard when you do this) then i work harden it with,some
healthy,well-placed strikes from a hammer. If you quench white
gold in alcohol it gets soft (some caution should be used to
ensure the alcohol doesn’t ignite). Good Luck,


I have always loved making Snaps and catches. I don’t always
bend the tongues for flexible bracelets or pearl clasps, I solder
two pieces together. The bottom section is slightly bigger than
the top and the top is in the shape of a cricket bat ( you can
tell I was trained in England). You then file a slight taper on
the end of the top section and solder it to the bottom. Leaving
about 1/2 mm protruding on the bottom section. You then file a
piece of chenier in half and bend it around the tongue. The
chenier forms the runner for the tongue. You then make the end
plate for the box fitting with the chenier still around the
tongue. When you have carefully fitted this so the tongue clicks
in tightly to the end plate mark the chenier at this point.
Remove the tongue and solder the chenier where marked to the
end plate. This then gives a runner for your tongue. You can then
fit it to your bracelet or pearl snap as you wish, putting on the
right shaped button for the tongue etc. The advantage of doing
it this way is that the runner makes the tongue very stable.

Reading this back I think I am better at showing people how to
do it than writing about it.

Chris Hackett