Colorado Art Castings Dewaxing, Pouring and Sandblasting Bronze Art Sculptures
Up to a dozen layers of ceramic are applied to the wax positive ensuring that the wax pattern and sprues are fortified by an outer ceramic shell that becomes the final mold after the shell is fired and the wax is "lost" (melted away).
The shells (still containing wax) are placed into the kiln and heated to 1600 degree F. At this point the wax is “Lost” (melted away) leaving a hollow ceramic shell that is ready to accept the molten bronze.
Art Castings uses electric melting in their bronze foundry because it is cleaner, faster, and offers more control over this important step. After the dewaxing we pour the molten metal (bronze at 2000 degrees or stainless steel at 2870 degrees) into the shell and allows it to cool. Art Castings pours bronze most every day.
The ceramic shell is removed from the metal and the sprues are cut off. Art Castings sandblasts the bronze sculpture to remove any ceramic remaining from the casting process to ensure a clean casting for the welding department.