PURPOSE: To form a product with flatness on surface required at a low cost by embedding lost foam material and a self-curing mold into molding sand, forming the mold and pouring molten metal into the lost foam material.
CONSTITUTION: The self-curing material is applied to the surface of a resin plate 8, and by curing the self-curing material, the self-curing mold 9 is completed. The resin plate 8 is removed from between the self-curing mold 9 and the lost foam material 7. The lost foam material 7 is incorporated into a flask 10 and also a spacer 11 having the same thickness as the resin plate 8 is laid on upper part of the lost foam material 7, and after laying the self-curing mold 9 on the spacer 11, the molding sand 16 is charged into the flask 10 to complete the mold 12. The mold 12 is turned over and zinc alloy 14 as molten metal at high temp. is poured into the lost foam material 7 from a cup 13. The lost foam material 7 and the spacer 11 are lost, and transferred on the self-curing mold 9 is filled up with the zinc alloy 14 the space and over the surface shape of the resin plate 8. After solidifying the zinc alloy 14, the mold 12 is disintegrated and a blank holder made of the solidified zinc alloy 14 can be obtd.
OKADA KAZUYASU
YAMADA MITSUNORI
