Soldering Copper to silver

Jewelry Discussion
1

Is it possible to solder a sheet of silver to a sheet of copper and
what kind solder would one use?

Thank you
Ken

2 
      Is it possible to solder a sheet of silver to a sheet of
copper and what kind solder would one use?

It is possible, and you can use silver solder. You will need to use
some heavy-duty flux, though, as copper oxidizes fast, and will load
the flux up with crud fairly quickly.

Lee Einer
Dos Manos Jewelry
http://www.dosmanosjewelry.com

3 
    Is it possible to solder  a sheet of silver to a sheet of
copper

Absolutely.

    what kind solder would one use?

Any grade of silver or tin/lead solder will work. The choice depends
on what you want to do with it. I used to always start with hard
silver solder in projects like this but after many years realized
that medium silver solder was probably better. The higher heat carries
more risk of the solder disolving into the piece. Silver solder is an
alloy of silver, copper and zinc. Add more copper and the melting
temperature drops. When you silver solder to copper or a copper alloy
the solder absorbs more copper from the material and the re-melt temp
is actually lower than the solder was originally. How much lower
depends on how hot and how long the solder was flowing. For this
reason reheating silver-copper pieces for later soldering can get
messy, because the solder melts again so easily. It is even worse
soldering silver to brass. Silver to gold does the same thing.

But if you want to prevent warping and keep the temper of the metal
you might want to consider using plumber’s silver/tin solder. Melts
around 450 F. This is great for sweating sheet together, but don’t
plan to forge or roll it afterwards and obviously you can forget about
adding anything later on with silver solder. You have to use a soft
solder flux and be sure not to leave any contamination on your
soldering bench because the stuff will eat right into silver or gold
if it is heated to hard soldering temperatures.

Stephen Walker

4 
Is it possible to solder  a sheet of silver to a sheet of copper
and what kind solder would one use?

Absolutely Ken, I have my students do it all the time. I would use
an Easy Silver Solder.

Joel Schwalb
@Joel_Schwalb

5

I as well agree easy silver solder. When I was at swest we sold a
plumbers solder in a tube call solder it worked on copper , brass,
nickel and bronze. No additional flux was needed . flows at 430
degrees…

Andy " The Tool Guy" Kroungold
Tool Sales / Technical
Stuller Inc
Phone 800-877-7777 ext. 94194
Fax 337-262-7791

6 
I as well agree easy silver solder. When I was at swest we sold a
plumbers solder in a tube call solder it worked on copper , brass,
nickel and bronze. No additional flux was needed . flows at 430
degrees..

I was sold a similar product for a similar challenge; the solder
ended up pitting the silver - or perhaps it was the paste medium in
which the solder was suspended? I always assumed I got the metals and
thus the solder too hot…

Roseann Hanson
Desert Rose Design Studio
www.desertrosedesignstudio.com
Tucson, Arizona
520-591-0508 voice/message
866-421-1813 toll-free fax

7 
    I as well agree easy silver solder. When I was at swest we sold
a  plumbers solder in a tube call solder it worked on copper,
brass,  nickel and bronze. No additional flux was needed . flows at
430 degrees..

This solder is an alloy of lead and tin. It will eat silver away.

8 
    This solder is an alloy of lead and tin. It will eat silver
away.

It will do that if you heat it to silver soldering temperatures, but
as long as you use it at temperatures it was intended for it works
just fine. I sometimes use plumber’s solder for attaching a raised
silver cup or bowl to a foot if I want to do it without annealing it.
This would not be kosher if it was all silver, but I am usually
mixing metals anyway. The plumbers solder we get now is lead free,
being 95% tin and 5 % silver, more-or-less. Takes a bit more heat than
lead-tin, but still very low compared to silver or gold.

If you are sloppy with this solder and any bits are in contact with
material that you gold or silver solder later on it will, as you say,
eat right in and be one hell of a frustration.

Stephen Walker

9 
This solder is an alloy of lead and tin. It will eat silver away.

As I understand it, this only happens if the solder is heated to well
above its melting point. Several soft solders are available that are
both lead and cadmium-free, and these might be safer to use.

Best,
Jessee Smith
www.silverspotstudio.com
Cincinnati, Ohio, where it is too pretty to be inside but I have sooo much
work to do…