EDM (Electrical Discharge Machining)

EDM burning ribs into lighting mold.

EDM or Electrical discharge machining is frequently used at Pacific Die Casting Corp. to make dies and molds for die casting. EDM, is especially well-suited for cutting thin ribs and other details that would be difficult to produce with a mill or other cutting tools. Often times with lighting die casting molds or die cast roof tile molds, intricate cuts are required. A graphite electrode must then be shaped and aligned in an EDM machine to produce the desired feature.

EDM is sometimes called "spark machining" because it removes metal by producing a rapid series of repetitive electrical discharges. These electrical discharges are passed between an electrode and the piece of metal being machined. The small amount of material that is removed from the work piece is flushed away with a continuously flowing dialectic fluid. The repetitive discharges create a set of successively deeper craters in the work piece until the final shape is produced.

Graphite Electrode

Electrical Discharge Machine at work.