Abstract: An electrical discharge machining device that is used for both rotational EDM, such as tapping, and the like, and for conventional or non-rotational EDM applications. The device includes a base support to which a carriage is slidably mounted, with a motor driven, rotating electrode assembly mounted thereon. A threaded lead screw is removably coupled to the upper end of the rotating electrode assembly and a mating threaded collar is removably mounted on the support so as to receive the lead screw and thereby advance the carriage as the lead screw is rotated. The lead screw and threaded collar are interchangeable with other lead screws and collars having different thread pitches, so as to regulate the advancement of electrodes having different thread pitches. An electrode is mountable both on the rotating electrode assembly and on the carriage itself.