The practical metal-worker's assistant : containing the arts of working all metals and alloys, forging of iron and steel, hardening and tempering, melting and mixing, casting and founding, works in sheet metal, the processes dependent on the ductility of the metals, soldering, and the most improved processes, and tools employed by metal-workers, with the application of the art of electro-metallurgy to manufacturing processes : collected from original sources, and from the works of Holtzapffel, Bergeron, Leupold, Plumier, Napier, and others ... (1851)
Byrne, Oliver · Philadelphia : H.C. Baird · leaf 299
used for drilling large holes, and also presents the choice of thevelocity best suited to each progressive diameter operated upon. Butwhere sufficient power can be obtained, it is generally more judiciousto enlarge the holes previously made with the pointed drills, bysome of the group of pin… … _ The ordinary pin drill, Fig. 339, is employed for making counter-sinks for the heads of screw-bolts inlaid flush with the surface, andalso for enlarging holes commenced with pointed drills, by a cutparallel with the surface; the pin drill is also particularly suited tothin materials, as the point…
Metal-work · Electrometallurgy · Metallurgy
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