Shaft linear motor driven with full closed loop control without backlash can use for a long time with high repeatability, low friction loss and high efficiency. contour matches closely between workpiece and cutting path. punch and die can match smoothly within 3μm clearance. flat type linear motor rotary motor rapid servo response can enhance the sensitivity of discharge gap control for the cutting speed up 8%~10% high repeatability in accuracy by applying the same cutting data on different machines, the consistence enhances the quality of workpiece and simplifies management procedure. high speed cutting by sd-master in stable discharge power stabilizes the cutting process, especially under high-speed mode. by cutting 100 holes of 6mm continuously,95.45% of all workpieces accuracy are within 3μm. cutting conditions are made by skd-11 with 30mm thickness by 0.25mm brass wire with 3 cuts under good temperature and environment control.