Good silver solder for steam engine work is 96% tin, 4% silver. It has melt
point of around 430 deg. I think. Harris Stay-Bright is a common brand..
Technically it is known as "silver bearing solder", I suppose because of the
relatively low silver content. It is used with zinc chloride / hydrochloric
acid flux, sold by Harris as "Stay Clean". PM Research specifies this type
of silver solder in their boiler kits - I recently built one. I'm not sure
about the "official" silver solder for jewelry work but 96/4 silver bearing
solder has worked well for minor jewelry repairs I have made. Incidentally,
96/4 is sold by Radio Shack as silver bearing solder.

The higher temp stuff, 800 degrees and higher is known as silver braze. It
is typically of high silver content, ranging upwards to 45% silver. Costly!
It is very strong - weld strength - probably wasted strength for jewelry
work though. Besides the higher temp would make it harder to handle without
damage to the jewelry.

Bob Swinney

"John Hofstad-Parkhill" wrote in message
...
I'll take my lumps. I did google. whineI've had a long week /whine

If you're building a model steam engine and it calls for silver soldering
parts together, what exactly is the solder in question?

I dabble in many things, as many of you do, woodworking, machining,
jewelry probably take up most of my interests. So, when in jewelry they
talk about hard/medium/easy solder (I have some, have used some) is that
the same silver solder used for live steam projects?

Sorry.