POCKET AND PEN KNIVES. Each knife, rough ly speaking, consists of two parts, the blade and the handle, but each of these, from the manu facturer's standpoint, is composed of a number of parts. The blade consists of the blade proper or cutting edge and its supporting back, and of the tang. or the portion which joins the blade to the handle. The handle, in turn, includes (1) the horn, ivory, or other material which is gresped by the hand, and which portion alone is technically called the handle; (2) the scale, which is the brass or iron lining of the handle; and (3) the spring, which, belides its primary purpose of controlling the blade in opening and shutting, also dotes the back of the lining.
The edge-tool steel from which pocket and pen knife blades are made is called rod steel: it is flat, of proper widths for the different sizes of blades, and of thickness one gauge greater than the finished blade. In the best goods the blades are forged and shaped by hand. In the case of cheap knives, the blades are pressed into rough shape by machines, then further shaped or forged by trip-hammers in much the same manner as that explained below in describing table-knii•es. Comparatively little machinery is used on the blades in either ease, except that the grindstones and finishing wheels are driven by mechanical power. The processes here described relate to high-grade goods.
.hooding is the name given to the rough shap ing of the blade at the first heat, and the forma tion of the tang is called hinging. After these two processes are completed the metal is heated for the third time, the blade again worked by hammer, and the nail-mark cut, which finishes the third or smithing process. All the forging is done by means of special hammers on special anvils, both imported from England. Choiling is filing the little nick just between the cutting edge and the tang. This removes a weak spot in the metal and serves as a guide in filing the blade flatwise. The blade is now shaped in the rough, but before it leaves the forge it must be hardened and tempered. Hardening is effected by bringing it to a red heat and dipping it in water up to the choil. The tang is left soft, so it may be readily filed. drilled, stamped with maker's name, and fitted in the handle. Temper (q.v.) is often accomplished by bringing the blades to a purple heat on a thin copper plate, resting on the fire of the forge. The blades are set on their backs, thus keeping their edges , furthest from the heat. The final work of the
forger or smith is to straighten crooked blades, if any, by means of light hammer-blows on the concave side of the blade.
Grinding is next in order. The grinder places the tang in a holder, which he grasps with one hand, while with the other hand, protected by a leather patch, he the blade against the rapidly revolving lower-driven stone. Racing irons, consisting of small rods of Norway iron, are occasionally held against the face of the stone to restore the rough surface and preserve its cylindrical shape. Material is the name given to all the separate parts except the blade. The material-maker presses out, or cuts out with dies, the steel spring* and the brass or iron lin ings, and fastens the tips or bolsters to the out side of the lining, in case the material forming the handle proper does not cover the tip ends of the lining. Cutler's work, curiously enough, in eludee, assembling, or putting together, the va rious parts of the knife. including drilling, filing, fitting, polishing, and huffing the handles. The material for handles embraces ivory, pearl. sil ver and gold, tortoise-shell, buffalo and stag horn, celluloid. ribber, California redwood, cocoa wood. and ebony. Polishing the handles is accomplished by power-driven built-up wood wheels, covered first with leather. then with a mixture of glue and emery. Buffing is effected on wheels in which the leather, emery, and glue give place to cotton cloth. fastened on edge around a wheel or spindle. Blade-finishing is done on emery wheels. much like the polishing wheels already described. except that the glue and emery are placed on very hard leather, in stead of on wood. Glazing. on these wheels, re moves the dirt and gives a glazed finish. Crocus finish is a superior glaze, or polish, requiring special wheels.
Sharpening is done by hand, on flat stones. The edges of the blades are held at an angle of 45° with the stone, a point that might well be borne in mind by all who attempt to sharpen old knives. The common practice of holding the knives flat on the stone gives a thin, easily bro ken edge. Finally. the handles are again buffed and the whole knife wiped, packed, and boxed. The ordinary knife of fair quality has now gone through about 100 operations, while the finest goods receive 200 to 300. It may be added that the processes involved in machine-forged pocket and pen knives resemble those described for table-knives in the next paragraph.