摘要 |
Form relieved rotary milling cutters such as 18 are rotated at unusually high speeds to produce high performance drill screws at improved rates of production. The cutters can be adjusted in a simple manner to achieve variations in the geometry of the drill point 17, and the speed of the cutters can be controlled carefully to maintain the quality of the products and maximize the life of the cutters. The screw blanks are held down by unusually high forces during cutting to prevent rotational and axial movement of the screw blanks. |