Hi Everybody,

My first post here, a question:

I'd like to make an alloy of 80% Copper, 10% Silver and 10% Zinc, to be poured into lost-wax molds (plaster/sand) on a small scale (eg. 10oz total). Copper and silver have reasonably close melting points (Cu 1981F and Ag 1762F), but Zn has a boiling point of 1664F, meaning it could boil off before the other two melted.
I'd like to know the best way to approach this, and would appreciate any ideas.
Here are a few ideas i have so far:

Could start with an available base alloy of 95% Cu / 5% Zn, and the pure silver, then add the remaining zinc and mix the alloy just before pouring. Does anyone here know what the melting point of 95Cu/5Zn would be? and would the Zn still boil out of the alloy as readily as pure Zn would? Will the mixing be likely to give problems (due to either silver or zinc)?

Does anyone have an idea what the casting behaviour of the 80:10:10 alloy will be (my mold is very simple)? Would a boric-based flux be a good idea?

Thanks for any input.

P.s., and yes i know about the dangers of inhaling Zn fumes.