Shaft tool with an adjustable cutting diameter, which permits improved handling. When the array starts the pre-charge cycle, the regular word line and latch P-channel bar signals both turn off and the complementary bit line pair is shorted together. The stylus includes one or more electrodes in a tip of the stylus. The core slide includes a core pin for extending into a die cavity of the molding or casting system, and a cam pin slot for receiving the two-stage shank of the cam pin such that one-speed relative motion between the cam pin and the slide base produces a two-speed relative motion between the core slide and the slide base. The blocking piece is arranged to abut a top of an expansion slot longer than the edge connector, to prevent the edge connector from being inserted into the expansion slot.