WATCHES AND CLOCKS. WATca MAKING BY MActuNERv.—The process now generally followed in making a modern watch is as follows : The plates, which are the foundation of the watch, are cut out by punches and dies, made specially for each design. In the main punch there are a number of small punches inserted, and so placed that the exact position of the holes required to be drilled are marked upon the plate. Then they are drilled, the plates are ground flat, the edges turned, and all parts to be turned out or recessed for wheels to set in, are done on special chocks, used in a proper lathe. The other parts, such as pillars, bridges, etc., arc then fitted and the plates put together. After all the fit ting is done, the parts are dismembered, and gilded, and in some instances nickeled.
The wheels are punched out in complicated dies, which act so as to perform several oper ations at one stroke of the press. After punching, they are placed on what is known as a wheel-cutting engine, a numbor of wheels —generally about 30 or 40 —being put upon an arbor at one time, so that the cutter passes through the whole stack and cuts one tooth in each of the wheels at each stroke of the ma chine.
After the teeth are cut, the wheels are bored, ground, and gilded or nickeled, as the case may be, after which they are ready to be staked or fast ened to the pinions. The pinions are cut in suitable lengths from a steel wire by a special cutter or die, made for that purpose, operated by a press similar to that used for the plates and wheels. These wire pinions are then chucked in a lathe, and a point, or center, as it is called, turned on each end, after which they are taken to another lathe, where, by a tool carried in a slide rest, they are turned down rough nearly to size. Prom this the pinions are set on dead centers in an automatic pivot machine, and turned to the exact size every way ; after that the teeth are cut, and then they are hardened. After being hardened, the teeth are polished by a machine known as a leaf polisher ; then the pivots, staffs, etc., are polished with the " wig-wag," a tool ,ell known to watchmakers and jewelers. All the parts arc similarly treated, begin ning with the punch and dies in the press, and pass along from one machine to another, until they are ready to be assembled in the finishing or setting up room, and put together to form a timepiece. There are about twenty
different mechanical departments in a watch fac tory, each performing a specific operation, and their products all center in the finishing room.
Tire Pinian-eulting Engine, manufactured by the Gesswein Machine Co., and shown in Fig. 1, is universally used for cutting the teeth in pinions for watches and clocks. It has a revolving tool head that carries three spindles. One of these drives a saw for cutting away the stock in ad vance of the other critters ; the second spindle drives a cutter to rough out the shape of the tooth, and the third spindle operates the finishing cutter, which gives the form to the teeth. The operation of this machine is simple and rapid.
The Aulonnelic Pivot-turning Machine shown in Fig. 2, a very ingenious piece of mechanism, also made by the Gesswein Machine Co., is for turning the staffs and pivots on all pinions, pal let arbor, etc. The wire is pointed and rough turned in a No. 21,- lathe ; it is then placed on dead centers in this machine and tarried very accurately to a length from shoulder to shoulder, and also in diameter. The turned staffs and pivots are then hardened, and after hardening, are ground and finished on the " wig-wag" ma chine.
The form of upright drill which is mostly ealled into use in the manufacture of the several parts of watches and clocks is that shown in Fig. 3. The spring action of the drill stock makes it specially serviceable for this fine work, and in the drilling of plates, bridges, etc. Fig. 4 shows a screw-cutting machine of the Gesswein Co.'s make, largely used in watch manu facture. A wire is fed forward through the chuck, which projects between two movable cut ting heads, and the tail stock has a horizontal screwed rod which acts as an adjustable stop for the end of the wire, in determining the length of screw to be cut. One of the slide rests or heads carries the thread-cutting tool, and the other, the cutting-off tool. This figure also shows a detached view of a tail stock for the same machine, with multiple stop spindles, to be used when it is desired to cut different lengths of screws without changing the tail stock.