Wire EDM is a method to cut conductive materials with a thin electrode that follows a programmed path. The electrode is a thin wire. Typical diameters range from .004" - .012" (.10mm - .30mm) although smaller and larger diameters are available. The hardness of the work piece material has no detrimental effect on the cutting speed. There is no physical contact between the wire and the part being machined. Rather, the wire is charged to a voltage very rapidly. This wire is surrounded by deionized water. When the voltage reaches the correct level, a spark jumps the gap and melts a small portion of the work piece. The deionized water cools and flushes away the small particles from the gap.
High-speed small hole edm is a specialized field of electrical discharge machining. A small .010" - .118" dia. (.25mm - 3.0mm) usually hollow electrode spins about a spindle much like a drill and drill bit (edm drill). The electrode is electrically charged by a servo-controlled generator producing the spark. Water based dielectric flushes through and around the electrode providing a controlled environment for the extremely small sparks to jump to the work piece. The sparks erode the surface of the work piece creating very small pockets. Eventually millions and millions of these microscopic pockets create the small hole. The size of the hole is controlled by the diameter of the electrode and the power settings. The location and depth of the ...
