Ian (and others), pity that Sir Winston was right; “The British and
the Americans are two peoples who are separated by a common
language”.
Our term “plumb solder” means that the solder has the same fineness
quality as the precious metal work-piece that it is intended to be
used with. Thus an 18K yellow gold plumb solder flows at a lower
temperature than an 18K yellow gold ring but is, in fact, 18K gold
itself, and a plumb solder for sterling is also 925 silver. The
witchcraft is in the alloy composition, no doubt the reason that
cadmium became popular.
Cheers,
Dr. Mac
perhaps I wasn’t clear: use the thermo-plastic to set up the jig so
to speak of wetted wadding and then solder…You are right, don’t heat
the thermoplastic (although there is a Vigor brand product called
"therma-shield", it’s a siliquar based material (greenish goo) and
can be heated with stones in place even (providing the stones are
completely covered and the soldering is a hit and run operation
RER
Thanks for your reply James.
The solder I was sent, that I liked so much WAS sterling plumb
solder and must have been made by PM West. Its credentials were
stamped into the panels but I can’t remember what it said as I cut it
up into tiny pieces to keep in separate jars but sadly I’ve run out
of the preferred hard plumb solder. Yes its melting point is
extremely close to that of sterling but I like it and didn’t
accidentally melt anything as I was careful. Thanks for the heads up
as to who makes it.
Helen
UK
The traditional way is to use clay, but long ago I switched to
sculpting wax, which models like clay and is much cleaner. You get
your clay or wax and smash it into a small pancake.
Brilliant suggestion John. I’ve made a few pieces like this and like
you suggest, after joining about three run into problems where
subsequent joint just don’t want to work, so I’ll look into what you
advise.
Thanks again.
Helen
UK
It’s a pity that none of the UK bullion suppliers seem to carry plumb
solder or even have heard of it, as it works beautifully and is
surely a better solder to use when having to send stuff off for
assay and hallmarking!
Helen
UK
Hi Helen,
The assay offices always take a sample of the solder used and for
silver, whether of Sterling or Britannia standard, the solder must
be at least 650 parts per thousand pure. Have you tried Manchester
Minerals for your solder (and other things)? Their relevant web page
is at http://tinyurl.com/3abp4e.
If you don’t know much about hallmarking, perhaps this site will
help http://tinyurl.com/34pu7u - it is the Birmingham Assay Office
site which I guess is the nearest to you (we have our own in
Sheffield).
I don’t think there is really much difference between the UK and US
solders, they are both basically silver/copper alloys with perhaps a
few trace metals and the ratios will be similar to achieve the same
melting temperatures for the various grades. The way you should
silver solder is to flux your work well, raise its temperature as
quickly as you can to a dull red so that it has little time to
oxidise and then raise it a bit more slowly until the solder flashes
through the joint. As soon as this happens you should remove the heat
as further heating can burn the metal. One reason you may have
trouble if you are building up a piece bit by bit is if solder from
one joint remains on the surface at the point you are trying to
attach another part. When solder melts onto silver it changes the
surface chemistry and this may be having an adverse effect. The other
thing that can cause a problem is if you heat the metal too hot
before the solder flows - as in if you have two pieces of different
size and you heat them both equally, by the time the larger part gets
to temperature, the smaller one will be overheated and the flux will
probably be burnt which effectively ‘dirties’ the surface so that the
solder won’t flow. You must organise your heating so that all the
pieces come to soldering temperature at the same time. Where you have
previously soldered joints, even if you have used the same solder as
you intend to on the next joint, there is a little latitude because,
as I mentioned before, the previously melted solder forms an alloy
with the silver which has a slightly higher melting point than the
new solder. It is, however, safer and better practice, to paint the
previous joints with ochre, rouge or whatever, to protect them from
the heat. I use white or yellow ochre artists water colour (the
cheapest I can find) which is very convenient to apply direct from
the tube.
Best wishes,
Ian
Ian W. Wright
Sheffield UK
I switched to sculpting wax
John try the florist clay. You know that green stuff at the bottom
of arrangements. Its the best so far. Just a tip.
Johneric
What I can't understand is that none of the UK suppliers I have
tried have even heard of "plumb" solder and keep suggesting to me
that it must be a brand name!!!
Hi Helen, do keep in mind that suppliers are have not necessarily
jewellery training or the passion that leads some of us to read and
learn and find out about other countries products and ways of doing
things. Yes, they are very knowledgeable about their products, and
very helpful too, great people to be on good terms with, but not all
knowing. cheers and Happy New Year to you all in the UK,
Christine in Sth Australia
Helen,
The melting solder onto each bit first - is that what you call
sweat soldering? It sounds worth a try anyway.
It’s a similar approach to that used when sweat soldering. For true
sweat soldering, you really only flow the solder onto one piece, then
heat the other piece until the solder flows between them. In this
case, you’re actually using the solder to “seal” the metal underneath
and keep it clean(er) to reflow without a lot of re-prepping needed.
In fact, you should be able to do it without intermediate pickling
and cleanup, unless you really keep the heat on it a long time when
you flow it the first time and build up a lot of oxidation.
When I have things that are really hard to position, this technique
frequently makes it possible without a lot of frustration.
There is a relative of the solderite pads, called Impressionite
soldering fixtures, made by Krohn industries. It’s a super-soft
soldering pad that is designed for fixturing like you’re doing. If
you are doing multiples of the same piece, you press the first one in
and get the indentations exactly right, then spray a fixative onto
the board. The fixative permanently hardens the board so the next
piece just goes into the indentations. I use it without hardening
many times, because I rarely do exact replicas… but when I do have
a line of exact pieces, I just spray that portion of the board,
leaving the rest soft.
Hope that helps!
Karen Goeller
No Limitations Designs
Hand-made, one-of-a-kind jewelry
www.nolimitations.com
John try the florist clay. You know that green stuff at the bottom
of arrangements. Its the best so far. Just a tip.
Oh wow! Johneric thanks! You mean the green stuff that soaks up all
the water? We call it Oasis in the UK (Oasis is the brand name). It’s
cheap enough too or at least it was when I was working in the
floristry industry.
Helen
UK