VIBRATION CUTTING DRILL

PROBLEM TO BE SOLVED: To provide a vibration cutting drill capable of increasing drill life and improving the cutting condition while the chip control is stabilized by vibration cutting. SOLUTION: In relation to the shape of conventional drills, the ratio of an angle of θ1 of the groove part, forming the groove ratio E of a drill, and an angle of the land part θ2 is increased to 1.3:1, the web thickness F is decreased to 0.26D in relation to the drill diameter D, and the edge angle G is enlarged to 140 degrees. Thus, compared to conventional drills, the chip control is stabilized, tool wear is improved, and the tool life is increased. Because of the optimum shape of the drill, the cutting conditions are improved and the cutting speed can be increased to 1.4 times conventional cutting speed, the feed speed of cutting can be increased to 3 to 4 times conventional feed speed of cutting, and the number of steps can be reduced to 1/3.