| 摘要 |
<p>A drill bit (2) for drilling holes along an arcuate path in a workpiece is provided with a cutting head where the cutting edges form continuous cutting edge (18,22,26 and 20,24,28) with radiused upper (30,32) and lower corners to permit free rotation of the cutting head as it is urged along an arcuate path. The bit is of a unique two piece construction (4,6) permitting selective materials to be utilized in the shank (4) and cutting head (6) portions.</p> |
