| 摘要 |
PURPOSE:To manufacture a pattern for casting with ease and excellent working efficiency in the stage of manufacturing the pattern for casting a press die by coating a mold release agent on the surface of a starting model, and forming a foamed urethane resin layer and expandable beads thereon to a specific thickness. CONSTITUTION:A mold release agent is coated on the surface of a starting model 7 templated from a master model. Polyol and isocyanate in vessels 8, 9 are mixed and the mixture is sprayed from a spray gun 10 onto the surface thereof, thereby forming a foamed urethane layer 11 having <=15mm. thickness. Ribs made of foamed styrene are adhered to the required position of the layer 11 to form the part corresponding to the reinforcing ribs of a press die. Expandable beads 13 made of expandable styrene are built up on the layer 11 to such thickness at which the thickness required for the press mold is obtd. by said beads and the layer 11. The assembly is removed from the starting model 7 by the effect of the mold release agent, whereby the intended pattern for casting is obtd. |
