The operation of the machine is simple and convenient. The principal axis is driven by DC servo motor or step-by-step motor with the advantages of speed adjustable, stabiliby good and noise lower. When the worktable moves, the light grating shows. The work liquid can be running water or pure water. (distilled water or deionized water) with better results. The machine mainly drills small holes with big depth-diameter ratio(200: 1) on stainless steel, chilled steel, strong alloy, copper and aluminum. The machine can also erode away the auger and taper tap broken in the work piece without damaging the original hole or threads.