Our Casting Process
You send us a wax model. Your model is carefully sprued and placed on a casting tree with other waxes that require the same casting temperature. The wax tree is placed inside a perforated stainless steel casting flask, which is then filled with investment. Once the investment sets-up, we eliminate most of the wax from the flasks before placing them in our ovens. Each flask is numbered and identified by the type of metal to be cast, casting temperature, customer(s) and wax weight. Now the flasks are ready to be placed in an electronically controlled oven that regulates the temperature of the flasks. We usually put the flasks in the oven in the latter half of the day so they will be ready the following morning.
At the appropriate time, each casting flask is removed from the oven and placed in a casting machine. Metal grain is poured into a graphite crucible positioned above the flask inside the machine, and the machine is sealed. Nitrogen gas is pumped into the casting chamber to prevent oxidation during the melt; vacuum is then turned on in the chamber. The temperature of the melting metal is regulated and monitored by the casting machine. When the proper temperature has been reached, the machine automatically releases the molten metal into the flask under pressure. The pieces are now cast.
Once cast, the flask is removed from the casting machine and quenched in water. The wax tree is now a metal tree. This tree is first cleaned with water pressure and then cleaned ultrasonically. The individual pieces are cut off the tree, re-cleaned and then sorted by client. Castings that are ordered unfinished are shipped to the customer; castings to be finished are processed accordingly.
Sophisticated modern technology and a highly trained staff enable Sierra Pacific Casting to provide a consistently high quality product.
