| 摘要 |
A mill has a front cutting portion with a plurality of peripheral cutting edges extending rearwardly from a front cutting end. Each peripheral cutting edge is adapted to generate a corresponding outer envelope of a body of revolution as the mill rotates around its longitudinal axis. At least one cutting edge is adapted to generate a cylindrical outer envelope; at least one cutting edge is adapted to generate a generally frusto-conical taper outer envelope extending away from the front cutting end while tapering radially outwardly; and at least one cutting edge is adapted to generate a generally frusto-conical dovetail outer envelope extending away from the front cutting end while tapering radially inwardly. |
