Wire Electrical Discharge Milling using a Wire Guide with Reciprocating Rotation

EDM is a useful method for machining hard materials. Particularly, ED-milling using a simple bar or pipe electrode is an attractive method to machine 3D cavities. However, it is difficult to suppress the electrode wear completely. On the other hand, in cases of WEDM and WEDG it is usually not necessary to consider the electrode wear. We can even use such materials like brass wire that wear easily. We developed a new method combining the advantages of ED-milling and WEDM/WEDG. It is named WED-milling (wire electrical discharge milling). In this method a wire guide with a hemisphere tip is used. The wire slides along the groove prepared on the surface of the tip. The wire guide is reciprocated in rotary state and moved along the designed path for generating the 3D shape. By this method, 3D machining similar to the mechanical milling with a ball end mill is realized. This method is free from the problems such as tool wear or the built-up edge in mechanical milling. In this paper, several machining properties of WED-milling are introduced.