Help! I have been soldering silver for 20+ years, and have dabbled
in gold. I have no trouble soldering silver, but I have been having
major problems soldering gold–even very simple jobs. What happens
is the solder will not melt, mush less flow, before the gold to be
joined. I can literally put the flame on the solder (which beads up)
until the gold beneath it melts, but the solder doesn’t.
I talked to a Rio Grande jeweler who advised me to flux the joint,
heat it to the temp that the solder should about melt, then apply
solder. I’ve started doing this, but I still have a horrible
struggle. Do other metals or contaminants on files used to shape
joints stop solder from flowing? I would deeply appreciate advice on
this; you can imagine how depressing this is when working on an
expensive ring. :-[
First I would suggest using cadmium free paste solder for the gold.
It makes it very easy to get the job accomplished. There is flux in
the paste, so there is no reason to add more. It flows very smoothly
and should solve your problem in an instant. It is available in all
karats and flow temperatures. If you are going to try again with the
sheet solder, I suggest that you do not heat directly on the solder
as that will dissipate the flux and then there is no way you can
make it flow. There can be contaminates from other sources that has
gotten on the sheet. Please gently sand the sheet solder, with a
new piece of sandpaper and then flux it fully. THEN cut the pallions
that you are going to use. Re-flux both the pallions and the piece.
Heat near the join and not directly on the solder. You should start
to see a melt and then the flow. Also, make sure the piece that you
are putting the solder on is clean and no residual pickle left on
the piece. You might want to pickle the piece, rinse and then dip
it in a super saturated solution of baking soda and water to totally
neutralize any acid that might be left on the piece and then rinse
again in running water to make sure there are no chemicals that
could interfere with the solder flowing.
I had the very same situation. I tried every torch adjusted in every
which way, all the fluxes and so on. I was very frustrated with the
amount of gold I had to scrap. After scanning the Orchid archives,
Idecided to ordersolder from Precious Metals West. Problem solved. I
suggest you contact them right away 1-800-999-7528 and get their
plumb solder.
No affliliation, just very happy to have my gold solder actually
flow! Natasha Wozniak
That same thing happened to me after a long day… I was unfamiliar
with the set up and I think I got the Torch fire to hot with O2
+Propane {I think the Propane burns a little Hotter than Acy?}.
Either that or Soder {14kSoder1550f; 10kSoder1425f } or Gold ( 14k
gold 1605f; 10k gold 1635f } So me way yea got your flow Pts
mixed. Just a thought.Also First post …
I had the same problem when I started on gold. I was using a
mixture of fluxes where the mixture had a lower useful temperature
range than any of the fluxes alone. I switched to a single high
temperature flux and it solved the problem. I prefer Battern’s.
Howard Woods
Usually in Eagle Idaho but in Denver this week.
The solder will not melt, mush less flow, before the gold to be
joined. I can literally put the flame on the solder (which beads
up) until the gold beneath it melts, but the solder doesn't.
Dale, Assuming you do not have faulty solder, what you describe is
totally logical, based on my own experience: If you direct the flame
on the solder, it will heat up, bead up and not flow. And often, by
the time the metal beneath reaches the flow temperature, the flux
has been burned off, preventing the solder from flowing at all. So
you add more heat thinking this is the problem. Eventually the gold
melts and you have a nice little mess to deal with. Been there, Done
that.
Here’s the scoop on solder. For solder to flow, you need only a two
conditions:
Clean, fluxed metal
Heat to attract the flowing solder
The key is that solder flows onto metal that is hotter than it is.
The gold beneath has to be heated, not the solder. When it reaches
the flow point of the solder, the solder will flow onto it.
I thought someone else would post this response, but I haven’t seen
it, so, for what it’s worth…
I had this problem too when I first started working with a little
gold. I think part of it is just getting used to the difference
between silver and gold. For example, gold doesn’t conduct heat
nearly as well as silver, so you can’t just assume the heat is
spreading throughout the piece, cuz it isn’t. It is building up
where your torch is, making it likely for that spot to melt if you
aren’t careful. Second, gold solder doesn’t seem to flow as readily
as silver, though perhapd I should try some of the ones recommended.
But here’s the main thing that solver the problem for me:
(drum-roll, please) I switched from 14k to 18k. It is prettier, and
it has a much higher melting point. I hate working with 14k, though
after using 18 for a while, I was comfortable enough with gold that
I can use it successfully. I used to melt so much gold! (sob) So,
along with everyone else’s advice, if you can, switch to 18, at
least for a while. 14 doesn’t save you any money if you melt it!
Dale, First I would suggest using cadmium free paste solder for the
gold. It makes it very easy to get the job accomplished. There is
flux in the paste, so there is no reason to add more. It flows very
smoothly and should solve your problem in an instant. It is
available in all karats and flow temperatures. If you are going to
try again with the sheet solder, I suggest that you do not heat
directly on the solder as that will dissipate the flux and then
there is no way you can make it flow. There can be contaminates
from other sources that has gotten on the sheet. Please gently sand
the sheet solder, with a new piece of sandpaper and then flux it
fully. THEN cut the pallions that you are going to use. Re-flux both
the pallions and the piece. Heat near the join and not directly on
the solder. You should start to see a melt and then the flow. Also,
make sure the piece that you are putting the solder on is clean and
no residual pickle left on the piece. You might want to pickle the
piece, rinse and then dip it in a super saturated solution of baking
soda and water to totally neutralize any acid that might be left on
the piece and then rinse again in running water to make sure there
are no chemicals that could interfere with the solder flowing.
Hi Dale, You didn’t say how large the pieces are, so I must assume
that they are relatively small.
There are a lot of variables, but you are right about
contaminants…the joints must be clean, free of filings and any
sort of dust. A boric acid/alcohol dip is necessary to prevent
oxidation from forming.The joints must be gap-free. You need to use
flux, but not gobs of it, just enough to keep the joint clean while
heating. You might practice on something which belongs to you, not
some expensive ring.
Bring the whole piece up to flow temperature but don’t heat the
solder. It should flow when the piece is hot enough. It might be
helpful to attempt to join some small pieces together,
sweat-soldering the joints and observing the changes as the metal
heats, and the appearance of the surfaces and flux becomes sort of
glassy looking. You may be using a torch tip which is too small for
the work that you are attempting. My apprentices have been taught to
think of the torch as a spray paint unit, and to paint the whole
piece with heat until it reaches soldering temperature. The fastest
results are achieved this way, and the longer the piece is hot, the
more difficult it is to get the solder to flow, as oxides form
relatively quickly in spite of your preventative efforts. A larger
tip, spraying heat over a larger area, will help you to get to the
proper temperature more quickly. Hope this helps.
What kind of gas are you using and are you using a neutral flame?
Oxidation is the enemy of successful joints. also the type of flux
you are using has loads to do with it also! Pripps is probably the
most successful and I have found that if you dissolve boric acid
into alcohol, dip the object and then burn it off, you will find a
lot less hassles in the polishing stage. if all else fails paste
flux works but is messy and your solder has a tendency to move. Also
heating the entire joint with a circular motion will help with
heating more evenly.
Thank you Alan…your explanation was concise and right on the
money!!!
By the way…for those out there just starting out in the world of
soldering…Alan’s comment is as applicable to silver as it is to
gold. Soooo many times a student will call me over and say…the
solder just won’t flow. I explain over and over that the ‘sink’ -
the largest piece being soldered to - is the place to direct the
flame, usually from the opposite side of the solder if possible.
Sometimes the ‘sink’ is not much larger than the piece being soldered
to it but…it still has to be heated first…no matter gold or
silver. The difference is, with silver the entire piece needs to be
heated. With gold only the area around the solder.
Another point. If for some reason the solder becomes blackened
(that is oxidized) because it was heated directly, just move the
torch away, daub on a bit more liquid flux and proceed to heat the
’sink’.
Happy soldering.
Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2
I don’t know what material most people use for a solder pick but the
one my father used was made of iron. I didn’t like it so I
experimented a little and settled on copper wire in a pin vise. Melt
an appropriate size piece of solder onto the end of the copper
wire,then heat the gold until it is near the melting temperature of
the solder. Use the pick to position the melted solder at the joint
and continue heating. Pure copper melts well above the temperature
of gold alloys so the copper wire doesn’t appear to dissolve in the
melted solder.
I had the same problem when I started on gold. I was using a
mixture of fluxes where the mixture had a lower useful temperature
range than any of the fluxes alone. I switched to a single high
temperature flux and it solved the problem. I prefer Battern's.
What about the ‘gassing’ of the zinc when the solder is to hot? …
Jimc