Boring Away Waste
Examine ; the shaded portion in the centre has to be cut away, and it will greatly facilitate the removal of this waste piece by boring a hole with a twist bit at the position shown. The twist bit should be about 1⁄8 in. less in diameter than the width between the gauge lines G. The easiest method of boring out this hole is shown at , which gives the correct position of the worker.
Fig. 85.—Vertical Boring previous to Chiselling.