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 59
ool operates best, is themost effective, and has the greatest strength,when formed with an angle of about 60°; and thissame angle, which in tools of this kind may becalled the angle of strength, can be formed to ad-vantage in all tools which are used to operate iniron or steel. The angle of 60° is… … Fig. 13. ameter of the circle, and this angle has 60°, andhas been found by experience to be the strongestand most durable form that can be given to aniron-cutting tool. If the reverse of this angle, oran indented V of the same form, be made in apiece of metal, it will form a gauge or guide bywhich…
Machine-shop practice · Tools
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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