Figure 27.—Auger-Bits. For smooth boring the lip bits are best. The side cutters project beyond the cutting lips to cut the circle ahead of the chips. For boring green wood the single-worm clears better than the double-worm bit.
Figure 28.—Extension Boring Bits. The cutting lips may be set to bore holes from 1⁄2″ to 3″ in diameter. They are used mostly in softwood.
Figure 29.—Ship Auger. This shape auger is made with or without a screw point. It will bore straighter in cross-grained wood without a point.