in a system for the production of molds for casting , a pair of pattern plates are disposed in an opposed facing relationship with a frame located therebetween in a manner whereby the opposing pattern surfaces of the plates , together with the frame , define an enclosed cavity within which a casting mold section may be formed . the frame is preferably provided with an opening through which the cavity may be filled with molding material which , after hardening , forms a mold section . after separation of the pattern plates and frame , the mold section is conveyed into assembled relationship with one or more other mold sections in order to form a mold for casting . pattern plates and frames may be arranged in a mass production facility to continuously form mold sections which , when assembled , will provide a mold stack for producing multiple castings .