| 摘要 |
A wood coring bit having a base, a central guide shaft, a sleeve extending along the guide shaft, a pair of scribing teeth on the surface of the sleeve adjacent to the work piece, which scores a track into the work piece as the bit rotates and raker tooth on the surface of the sleeve adjacent of the work piece which is aligned to follow in the track scored by the scribing teeth and to cut and lift out the wood from the scored area. A helical slot extends through said sleeve from the raker tooth to receive the chip. A shank aligned with the guide shaft is used to connect the bit to a drill.
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