Electrical Discharge Machining (EDMing)
Discharge Machining or EDMing is a machining method used to machine any conductive materials including hard metals which are difficult to machine with traditional techniques. EDM can cut small or odd-shaped angles, intricate contours or cavities in pre-hardened steel without the need for heat treatment to soften and re-harden them. EDM removes material by a series of rapidly recurring electric arcing discharges between an electrode (the cutting tool) and the work piece, in the presence of an energetic field. The EDM cutting tool is guided along the desired path very close to the work piece but it does not touch the piece. Consecutive sparks produce a series of micro-craters on the work piece and remove material along the cutting path by melting and vaporization.