As a pioneer of shell molding in the United States our casting operation has been recognized by the American Foundry Society and by " Modern Casting Magazine". All castings poured at Graham-Whiteare made using the shell process, also referred to as the Croning process, in which a resin coated sand is either dumped on a heated pattern to produce a mold or blown into a heated core box to produce a core. Shell molding produces castings with excellent surface finish and tighter tolerances than other sand casting processes. In general, dimensional tolerances are held to +/-0.040" for pattern dimensions and +/-0.015" for cored dimensions. The shell mold process is used to cast ten different grades of gray iron, three grades of ductile iron, five grades of brass and bronze alloys, and five grades of aluminum alloys. Casting capabilities allow up to 35 lbs. in non-ferrous alloys and up to 70 lbs. In ferrous alloys.