| 摘要 |
PURPOSE:To permit easy working and to form a back bar to an exact shape by pouring a molten conductive material into a casting mold contg. a master made by pouring a patternmaking material to the surface of a work made of a sheet metal into a prescribed shape thereby forming the back bar. CONSTITUTION:The patternmaking material consisting of molten silicone rubber, etc. is poured to the surface of the work made of the curved sheet material to form the master 3. The master 3 is contained into the casting mold 5 and thereafter the molten conductive material consisting of copper or beryllium copper is poured into such mold to form the back bar 6. |
