Small hole EDM is a specialized component of electrical discharge machining. A small 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 spark to jump to the work piece. The electric spark erodes 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. The location and depth of the holes are driven by CNC ISO codes, reducing and eliminating operator error.