the video Silver Paths The art of Filigree
shows an artist preparing silver solder with cadmium, silver and
He uses 3 g of cadmium powder, silver and copper and mix all of them
in his hand.
But cadmium is poisonous: in there a real risk using cadmium?
I want prepare a low melting point solder: what is the best
composition for it?
cadmium is very dangerous and there are many other metals and
chemicals that are poisonous when working in the jewellery industry
so always work in a well ventilated area.
This way you are protected otherwise you are destined to have cancer
or a serious illness.
I would tend to agree with Hagop here. However, I used cadmium based
solders for many years and I am cancer free. knock knock...;They
flow better than any other solder I have ever used.
Cadmium containing silver solders (brazing alloys) are still
available from different manufacturers but their use is becoming
more and more restricted by due to different National and
International regulations. Their use is not something I would
recommend for jewellery items.
The lowest melting point cadmium-free silver solder (brazing alloy)
is one of 55% silver, 21% copper, 22% zinc and 2% tin. This has a
melting range of 630-660C. It conforms to EN1044 AG103 and is known
by various different trade names; Johnson Matthey Silverflo 55,
Thessco M25T etc. There is no direct US equivalent to this alloy,
the closest is B-Ag 7 which contains a nominal 5% tin and is a
slightly more stodgy alloy regarding its flow characteristics.
10 grams of sterling silver
1 gram copper
3 grams white silicon
6 grams mossy zinc
Melt all metals into an ingot either in a well in a charcoal block,
or a crucible. Then file with a bastard file. I got a really fine
inside ring file burr for my flex shaft after losing too much skin
on my knuckles.
Where to find the last two metals? Do a google search. I have enough
of each to last me a lifetime, and can't remember where I found them
via google. Also the white silicon may come in large chunks. I pre
file them before I melt it all. The chunks will not melt into the
other metlas no matter what you do, I used an oxy acetylene casting
torch and got frustrated.
If you want to save all the trouble there are two places to get the
powder solder already made. Victoria Lansford sells her version.
Beth Katz in So Florida (Unique Solutions) also makes the powdered
solder. Many swear by Victoria's. I swear at it. I prefer Beth's. It
is a bit more per container for Beth's, but Victoria's is 1/2 ounce
and Beth's is one ounce.
Victoria's has the flux mixed in, and Beth's you need the white paste
solder for it. It all comes down to what you like. I've used both. I
demo both. I let the people I teach decide for them selves.