摘要 |
A metal mold is prepared by an electrical machining process wherein one of a base metal mold and an upper metal mold is electrically shaped by using an electrode having a desired shape on a surface thereof facing the workpiece, and the electrode then is fitted into the shaped metal mold to make a composite electrode of the two, and if necessary, the opposite surface of the electrode is also shaped. The other metal mold is then electrically shaped by using the composite electrode having the desired shape. With this invention, it is possible to provide a metal mold for thin articles, such as plastic articles.
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