The mechanic's tool book. With practical rules and suggestions for use of machinists, iron-workers and others (1868)
Harrison, William B · New York, D. Van Nostrand · leaf 112
is ap-plied, will give an index of the proportion of thelines of the point as regards their equal length,and this measurement is easily ascertained by theeye. This exactness is important in a good cut-ting drill, as both sides must perform their pro-portion of the work. The cutting angle shouldmeet… … Fig. 24. cutting angle. When the drills are dull and areground, let the same gauge which is shown in Fig.24 be applied to ascertain the form of point. Another method of using the drill is to insertthe back or dead center in the countersink at theend and hold it fast with a wrench, and apply itto…
Machine-shop practice · Tools
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
