Hello All I’m a person still on my training wheels in the
jewellery field and I’m struggling with multiple soldering. The
solder recedes every time I heat the object. I imagine this is
pretty normal but I’ve been hearing there are ways to avoid it
(ie: papermate white out and heat sinks). Can someone please
tell me what a heat sink is?
Thanks
Cal
Virtually all supply (jewelry) houses offer a form of “no flow”.
This is a liquid that is applied to a solder joint before
additional joints are soldered. It will prevent the original
solder from flowing and disolves in an ultrasonic.
Hello out there! A heat sink is something that draws the heat
away from the area you are soldering, causing it to take longer
to bring the piece up to solder flowing temperature. That
something might be a third hand used to maintain the position of
the piece, or a soft firebrick used to support your work or even
something called “Cool Jewel” which can sometime be used to
protect the stone from the heat necessary for repairs. SR in
Coronado
Dear Cal, When you say, “The solder recedes every time I heat
the object,” I am not clear what you mean. Are you saying that
you solder something and then without filing, sawing, sanding,
polishing or anything else, when you heat it again is shrinks
back? Please be more specific so we know what you are talking
about.
A heat sink is an object, usually metal, that draws heat away
from the area being heated. For instance, when a pair of
tweezers is attached near the area to be soldered, it heats up
instead of (or before) the work. Sometimes this can be a useful
technique and sometimes it gets in the way. There is a lot more
to be said about it, but that is the general idea.
Alan Revere
Revere Academy of Jewelry Arts
San Francisco
Hi Cal – There are lots of beginners here – I think I’ll be one
forever – I learn something new just about every day… A heat
sink is anything that will draw heat away from the object you are
heating – it can be a pair of tongs that you use to maneuver a
piece of metal while you are soldering or even the mesh screen on
top of the tripod…
Solder will go where the heat goes – if your solder recedes,
then draw it back where you want it by moving the torch from
where the solder is to where you are wanting it to go. Sometimes
a solder pick will help spread it around as well.
There are a number of materials that you can use to keep solder
from moving and undoing all of your work: yellow ochre, liquid
paper (the water-based kind only), red rouge.
Other things you may want to consider when you have multiple
soldering operations in one job is whether you can use binding
wire to hold your pieces together and do multiple steps at the
same time; another thing to consider is starting with hard
solder and stepping each soldering operation down to medium,
easy, etc. Each of these solders flows at a different temp,
which may allow you to do more than one solder step and
controlling it through the heat of your metal.
Laura
lwiesler@att.netPeter:
If your solder won’t flow it can be caused by a contaminate on
the surface, not enough heat or oxidation formed on the metal by
inadiquite fluxing. First and formost, be sure your piece is
throughly cleaned eather by ultrasonic and steam or simply by
scrubbing with a good cleaner mixed with warm water and rinsing
throughly. Dry and coat the entire piece with boric acid and
denatured alcohol. Mix it so the solution is milky white. Brush
or dip the piece to throughly coat the piece and light it to burn
off the alcohol. The remaining coating of boric acid will melt
when heated and seal off the metal from oxygen thus preventing
black scale which is the discoloring or blackening of the piece.
If you flux your joints well and heat watching for the metal to
begin to glow red, you should have no further trouble getting
the solder to flow.
A heat sink is usually a metal object of greater mass than your
piece placed between your soldering and a heat sensetive stone,
tempered spring metal or other solder joint you don’t want
disturbed. You might want to use solders of widly varying melting
points in multiple solders near each other. Use the hard first
and go down. Paper Mate white is a correction fluid used for
typing(something I use a lot as you might guess judging by my
typing.) When applied to an engraved pattern on a ring or a hinge
and heated, it burns and prevents solder from flowing there. I
have always used yellow ochra powder mixed with a little water
myself however.
Hope this helps;
Steve
Are you soldering your first joints with hard solder, moving on
to medium, then easy? I’ve found that carefully planning my
soldering this way helps to avoid the joints remelting!
I believe what you refer to as the solder “shrinking back” is
from cleaning the solder joints and then reheating (perhaps to
solder another joint), which will indeed cause the solder to
shrink into the seam of the first soldering. All soldering
operations should be completed FIRST before you file and clean
up any of the solder joints.
John g
Virtually all supply (jewelry) houses offer a form of "no flow". This is a liquid that is applied to a solder joint before additional joints are soldered. It will prevent the original solder from flowing and disolves in an ultrasonic.
An inexpensive way is to simply use nail laquer - any colour
could be used. It normally comes in tiny bottles with a nice
little brush in the lid. Put it on where you don’t want the
solder to flow before you put on the flux. When the nail laquer
gets hot it contaminates the metal thus preventing the solder to
go there. The remainders are easily removed in the pickle. It
has worked for me for years.
Kind regards
Niels L=F8vschal, Jyllinge, Denmark
@L_F8vschal
Typing correction fluid is a terrific medium to prohibit solder
flowing where you don’t want it. But the fumes generated are
highly toxic. It probably won’t bother you if it isn’t used in
large quantities or too frequently, but wearing a protective mask
is probably a good idea.
To avoid the toxic fumes, use the Water Based correction fluid,
I think BIC makes one. (There is more than one Manufacturer of
the water based kind.)