Miniature three-edge drilling bit

摘要: The utility model provides a miniature three-edge drilling bit mainly used for the operation of printed circuit board, comprising body portion and handle portion. is holes on board fixing hole machine. tip end milled into three cutting edges with same angle ridge formed each two intersecting ridges forms conical point. sides respectively form edge groove Two opposite portions large crumb discharging space rapid discharging. force equally distributed thus service life relatively improved.