| 摘要 |
PURPOSE:To prevent generation of shrinkage and to improve yield by increasing the thickness of only the riser part of a casting mold by spraying after dewaxing of the mold by lost wax thereby improving the holding effect of the riser part. CONSTITUTION:A pattern is obtd. by wax and is dipped in a slurry to form a casting mold wall 5. The mold is dried and dewaxed, then a mixture composed of the slurry used for manufacturing the casting mold and paper clay is sprayed to the part upper than a gate part 2 by a sprayer to form a casting mold wall 6 for holding. The spraying and drying are repeated to attain a prescribed thickness and if the casting mold is calcined thereafter, the paper in the wall 6 burns and this port is made porous. The holding effect of the riser 3 is thus improved. |
