Soldering Hi Charlyhstl~
Here is what I do. I rough up the wires to be solders (slightly) with a heatless wheel. Line the wires up w/aligator clips.I first put flux on the wires to be joined then very carefully add heat shield to the areas around the flux, don't touch heat shield to flux! Personally I solder on a little more silver then necessary, so that I make sure I have a good weld all the way around. Then trim up the joint with a heatless stone and polishing wheel, both with a handpiece.
Make sure you make a divet in the plaster where the joint will be soldered so that it allow the silver to flow. If the wires are right up against the plaster, often you won't get a good flow of solder.
Hope this was helpful,
trisha