Metal Casting Process For Metal Sculptures

Lost-wax casting, also known as lost-wax casting, is based on a very simple principle: a wax figure is made, then a layer of heat-resistant model material is poured onto it using a mold-forming method. The mold is heated until the wax begins to melt, and then dried, leaving a hollow shape that resembles the wax figure. Molten metal is then poured into this hollow. Once the molten metal cools, the mold falls off, and a replica of the wax figure is created. Lost-wax casting is a major invention in the history of metallurgy, as the precision and complexity of its cast shapes are unmatched by other casting methods.

Ceramic shell casting is a relatively new technique, introduced from industrial casting in the mid-1960s, and is used in at least 95% of commercial art foundries. A ceramic shell is fixed onto colloidal silica, the wax figure is immersed in the slurry, and then a layer of powdered refractory material (plaster) is applied. The mixture can be allowed to air dry or aided by a fan. This process is repeated about seven times, forming a shell 3-8 inches thick around the wax figure and gating system. By using steam or rapid heating, the wax figure will melt completely, while the outer shell is heated to a temperature far higher than that of the solid mold. This also removes any remaining wax and, more importantly, allows the ceramic components inside the shell to be burned, making it more robust and able to withstand the pressure generated by the molten metal.