United
Precious Metal Refining, Inc.
Ag Casting Grain Type "D" & "14"
Covered under one or more of the following #'s. U.S. Patent #
4,973,446, # 5,039,479
Sterling Silver "D" and "14" are proprietary deoxidized sterling
silvers, designed to reduce fire scale and porosity. By applying the
"Know How" that has granted us two U.S. Patents, we have developed
the first and only deoxidized Sterling Silver Casting Grains for
investment jewelry casting. Please read the instructions thoroughly
to obtain best results.
Melting: Traditional methods of melting regular sterling silver
I.E. (as cool as possible) will cause a variety of problems. Most
failures with these sterling products are caused by too low of a
melt temperature. Customers familiar with silicon deoxidized gold
casting alloys should have less trouble adjusting to the appearance
of these silvers.
MELTING
Temperature Range 980° - 1030° C.
1800° - 1900° F.
REMELTING
We recommend a 50% fresh mix. Our sterling silver replenisher
can also be used without adding fresh.
FLUXING
It may be necessary to flux these silver melts. We recommend
Boric Acid. Do not use Carbon Containing Fluxes or Charcoal. Skim
any surface oxides off the surface before stirring.
QUENCH TIME
15 - 20 minutes.
HARDNESS AND HEAT TREATMENT
The Sterling Silver "D" can be hardened further by heat treatment at
300° C / 575° F for one hour, and air cool. The hardness of the
Sterling Silver "14" can only be marginally improved with heat
treatment.
INVESTMENT REMOVAL
Most standard investment removers will successfully remove the
investment powder. The best solutions are the sulfuric and
hydrofluoric based products. UNITED's Brite-Cast Investment Remover
also works well, although it is less aggressive and will take
longer.
FLASK TEMPERATURE
Use your regular flask temperatures.
FIRE SCALE
Fire scale is completely eliminated.
CYANIDE TREATMENT
Not recommended.
TECHNICAL ASSISTANCE
Always available…
Call 1-800-999-3463 / 1-800-999-FINE
E-mail / doc@unitedpmr.com
Web-Site / www.unitedpmr.com |