Lost foam pattern for molding and method of making same

A method of manufacturing a molding product by using an evaporative foam pattern, made out of synthetic resin which is decomposed and gasified by molten metal, comprising the steps of:

• providing a runner portion foam pattern so as to extend vertically, said runner portion foam pattern including a hollow portion and a base portion;
• providing a plurality of short-sized gate portion foam patterns integrally on external surfaces of the hollow portion of the runner portion foam pattern;
• providing a product portion foam pattern;
• positioning and fixing a jig member to an upper opening portion of the runner portion foam pattern;
• attaching a handling device to the product portion foam pattern, said handling device being movably mounted to the jig member at its end;
• coating an adhesive on edge surfaces of said short-sized gate portion foam pattern;
• adhering the product portion foam pattern to the external surfaces of the hollow portion through the plurality of short-sized gate portion foam patterns so as to provide the evaporative foam pattern by closing the handling device;
• burying the evaporative foam pattern in a sand mold;
• and
• pouring molten metal into the evaporative foam pattern through the upper opening portion of the runner portion foam pattern.