| 摘要 |
The present invention provides a device for forming countersinks on a piece of material at a non-perpendicular angle. The device can be easily adjusted to vary the depth of the hole to be drilled, and is of simple construction. The device is an elongate tube that defines a continuous opening along i ts central longitudinal axis. The opening extends through the first and second end, and is adapted to receive a drill bit therethrough. The first end has at lea st one cutting edge for forming a countersink. The second end defines at least one slot parallel to the central axis and extends along the tube outer surface, to allow circumferential compression of the tube when squeezed by a drill chuck.</SDO AB> |
