Abstract: A support base has adjustable slides mounted thereon. A cam arm is mounted at one end on a piston rod that is used to cause vertical movement of the cam arm. The opposing end of the cam arm has a bore that rotatably receives a sleeve therein. An electrode holder is pivotally mounted in the sleeve such that one end of the electrode holder extends beyond the end of the sleeve. The electrode holder is movable between a first normal working position and a second non working position that corresponds to movement of the cam arm. A drive motor and belt are engaged with the sleeve to cause rotation of the sleeve, electrode holder, and electrode to perform machining operations on a workpiece that the electrode is inserted into.