From other threads regarding the joining of aluminium with these
special rods you can buy, they are apparently very high in zinc. It
would be interesting to see if you could join aluminium to steel or
galvanised steel with them.

Checkmate wrote:

On Sat, 13 Dec 2003 20:36:46 GMT, Don Bruder put forth the notion
that...

In article ,
(Ted Shoemaker) wrote:

Hello,

I have some basic questions about soldering.

If I want to make a small art project with common metals
(steel, copper, aluminum, etc.), what do I need to know about
soldering?

About 25 years ago, I learned a very few basics about soldering
electronics.
One was that you use different solders for plumbing, electronics, and
jewelry. But which kind do you use for art? (Also, it's likely the
technology and materials have changed since then.)

Please respond to the newsgroup and not to my email.

Thank you very much,

Ted Shoemaker

Well, first thing is that you don't solder steel or aluminum. Period.
You can gob on wads of solder and stick steel or aluminum pieces
together the way you'd stick, for instance, chunks of wood together
using a handful of clay - They'll be joined, yes, but don't count on
*ANYTHING* resembling structural strength, and you'll never get anything
even remotely like a proper solder joint out of the attempt. The metals
just aren't compatible (The solder simply won't "wet" them, so it can't
"grab on" the way you're probaby used to from electronics work) so it's
one of those "ain't gonna happen" things.

Until relatively recently, when lead-bearing solder was either outright
banned, or severely restricted for use in potable water plumbing work,
the main difference between the solders used for plumbing and
electronics work has been the flux - Plumbing uses acid flux,
electronics uses rosin. This is due to the differing ways that plumbing
and electronics tolerate (or fail to tolerate...) the inevitable
corrosion from acid left behind by anything other than an *ABSOLUTELY
PERFECT* cleanup job. Electronic gear doesn't like acid traces on the
board, and generally dies in fairly short order if acid flux is used.
This is partly due to the comparatively thin layers of metal being
worked with, and partly due to electrolytic action that starts happening
when the device is powered up. Plumbing, on the other hand, is heavier
gauge metal, usually homogenous (only joints are copper-copper, with no
possibility of copper-iron, copper-zinc, or similarly heterogenous
joints) and not subject to carrying current, so it's much more forgiving.

Jewelry is *USUALLY* done with silver solder, which, as the name
implies, usually means that the solder has at least some silver content
to it. It's a harder solder (in terms of the comparative placements each
would have on the Moh's hardness scale), and often, if not usually,
requires a higher heat to work with than tin/lead soldering; You can
solder using tin/lead solder with, depending on the exact alloy,
anything from a kitchen match to a propane torch, while silver solder
often requires a MAPP gas torch to get into the heat range needed to
make it flow properly, and for the *REALLY* hard silver-solder alloys,
might even require a small oxy-acetylene rig.

As far as "art" soldering... shrug Never encountered the concept, but
at a guess, I'd say that if it involves steel, it's probably actually
brazing (which is BASICALLY soldering with brass or bronze solder,
rather than tin/lead or tin/silver), and if it involves aluminum, it's
more likely TIG welding.


There's a rod for aluminum to aluminum now that works pretty well, but
it won't stick it to any other metal. It's more like brazing than
soldering, but you can do it with propane or MAPP gas.