MANUFACTURE OF MODEL FOR PRESS DIE

PURPOSE:To suppress the generation of heat during solidification of gypsum and to prevent the deflection of a model serving as a standard for the purpose of manufacturing model for a press die by mixing with an impurity in a gypsum material to be coated and solidified on said model and increasing the amt. of the water to be mixed therewith. CONSTITUTION:A metallic flask 13 is provided according to need above a master model 12 formed by an epoxy resin or the like on a pipe flask 11. A gypsum material which is mixed with an impurity 14 consisting of lightweight aggregate and gypsum lumps or the like and contains water in the amt. larger than usual is cast onto the model 12 and is solidified. The generation of the heat during solidification of the gypsum is thus suppressed and the heat of evaporation is deprived of by the water, whereby the heating up of the material is prevented. As a result, the deflection of the model 12 is prevented and a model 15 for a press die of light weight having the accuracy of the reproduction surface at a high level is obtained.