When we solder a brass domed/stamped object to a flat sterling
pendant using Stay Brite solder and flux we are getting a rough,
very deep, approximately 1mm wide line all around the object in
The first thing I would try is to use a mechanical means of keeping
the solder from spreading. In Alan Revere’s book “Professional
Goldsmithing”, he creates a groove just inside the applique to keep
solder from leaking out and spoiling the base to which he is
An alternative would be to try a different soft solder, perhaps even
one with lead. Since you are not doing any other soldering or
heating, you have more options for the connection.
Another suggestion is to greatly reduce the heat you are using with
Sta-brite. It needs very little heat to work.
Another idea is to coat the silver with yellow ochre or some other
stop to keep solder from flowing.
When I did a production run of sterling and brass images for award
belt buckles, I used conventional easy solder, a good anti-firescale
agent and careful heating. It took a peroxide pickle to remove the
pink stuff on the brass after soldering. I then tumbled the pieces in
two stages of abrasive media and finished with stainless steel in my
big rotary tumbler. They are nice looking buckles. I didn’t groove
the brass and had absolutely no solder leakage.