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 122
ermed a counter-bore, or pin drill, or, as it is called in someshops, a sweep. The tool is fitted to the chuckin the same way as the drill and is held in likemanner by the shank ; the opposite or cutting endis flattened and turned to a diameter exactly ofthe size of the hole required. This flat… … Fig. 27. must enter. The cutting lips, <?, c, of the tool aresloped back with a file so as to form a cuttingedge, of about 60°. On the advancing edge orside, a recess, 0, is hollowed with a small roundfile so as to give the cutting lip more of the formof a cutting tool. The end of the tip is…
Machine-shop practice · Tools
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