EDM WIRE & SINKER:
An electrical discharge machine. Electrical discharge machining (EDM), sometimes colloquially also referred to as spark machining, spark eroding, burning, die sinking, wire burning or wire erosion, is a manufacturing process whereby a desired shape is obtained using electrical discharges (sparks).
EDM wire cutting uses a metallic wire to cut a programmed contour in a work piece. Extrusion dies and blanking punches are very often machined by wire cutting. Cutting is always through the entire work piece. To start machining it is first necessary to drill a hole in the work piece or start from the edge.