INSTRUCTIONS FOR STERLING SILVER CASTING GRAIN

UNITED’S STANDARD STERLING SILVER CASTING GRAIN may be used for investment casting or cast in ingots for sheet and wire stock.

CASTING TEMPERATURE - Temperature range 960 – 980 Degrees C. / 1760 to 1796 Degrees F.

FLUXING – It may be necessary to flux this melt. Boric acid is the recommended flux. Do not use fluxes that contain saltpeter or sodium carbonate. Skim off any surface oxides before stirring.

CRUCIBLES – Do not use Silicon Carbide crucibles with any sterling silver.

QUENCH TIMES - Wait 15 to 20 minutes before quenching flasks.

FLASK TEMPERATURES - Use your regular flask temperatures.

INVESTMENT REMOVAL - Most standard investment removers will successfully remove the investment powder. Hot sodium bisulfate solution (Sparex) or a 10% Sulfuric Acid pickle solution will remove the black oxide on the surface of the castings.

HEAT TREATMENT – To improve hardness, furnace heat treat at 300 Degrees C / 575 Degrees F for 1 hour and air cool.

REMELTING – We Recommend a 50% fresh mix for remelting.

SOLDERING – Use normal soldering technique.