For blind hole tapping operation was cut timber, the screw tap and hand tap the general difference is that ordinary hand taps it into a straight groove, and Spiral Tap is a spiral, spiral tap during tapping, to increased rotation of its spiral groove can easily put the iron out of the hole, so iron residue or blockage in the groove, causing broken tap, the blade crack, it can increase the life of taps and cutting out the highest accuracy of the thread cutting speed can speed up 30-50% over straight slot tap. Spiral flute tap used for CNC machining centers drilling blind hole, processing speed, high precision, chip better, neutral good. Lo pointed Taps tolerance undercut the front, for the processing of the through hole.