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The shell molding process is a comparatively new method of producing castings with a smooth surface finish. It lends itself to close dimensional tolerances that are much lower than can be obtained by the conventional green sand method of casting. This new molding process eliminates machined finishes in many cases. It cannot be overemphasized that extreme accuracy is necessary in producing the shell molding pattern equipment, for which we have tried to lay out the procedure by the following methods.