MASS PRODUCTION OF WATCHES The use of duplicating machinery for watchmaking began in America with Henry Pitkin of Hartford, Conn., in 1838, but with no stress on interchangeability. The American Waltham Watch Company early in 1853, in Boston, produced watches in quantity. This was the parent organization of some 3o odd American fac tories, of which, in 1928, only the Elgin, Hamilton, Illinois, How ard and South Bend factories existed, producing from about ioo to some 4,000 watches each, or a total of 8,000 to ro,000 per day, over 3,000,000 per year. The present-day automatic machinery has been developed by many inventors and designers among whom are Sherwood, Webster, Marsh, Stratton, Moseley, Woerd, Hart, Church, Ohlson and Gabriel.
The New Haven Clock Company then began making a clock wound from the back, small enough to be carried in the pocket. and this was followed by a smaller one by the Waterbury Clock Company. It was due, however, to the merchandising genius of Robert H. Ingersoll that enormous production has come into being. His business passed in 1922 to the Waterbury Clock Com pany. Other companies followed and of those in America con tinuing in 1928 the Western Clock Manufacturing Company, the Ingraham Company, the New Haven Clock Company and the Ingersoll Watch Company, each produce daily from 5,000 to 14,00o watches or a total of about 1o,000,000 per year. The size of the cheap watch has been reduced from an 18 to a 12 and even to a 6 size. An o size wrist watch has been manufactured. (The sizes of movements are designated by 3oths of an inch over the o size which is inches.) Recent Improvements.—Many improvements have been made in the design of cases, by chromium plating and luminous dials. While each factory has its own processes in detail, the
example from one factory in which there are 117 pieces is de scribed here as being fairly typical. Forty of these pieces are made on screw machines, 38 in presses and 39 on forming or head ing machines. The frame plates are blanked from sheet brass at the rate of 25,000 to 5o,00o per day per machine, pierced 15,000 to 16,000, reamed 2,000 to 3,500 and finished 12,00o to 54,000. The wheels stamped finished from sheet brass by compound sub press dies come through at a rate of 50,000 to ioo,000 per day. In this press the holes are pressed downward and the wheel ward simultaneously, the severed parts coming back in original position so that the sheet may be pushed onward for duplications. The small toothed wheels (pinions), are produced in three ways : (I) by milling the teeth from a solid blank in a screw machine ; (2) by turning down for arbor and pivots from pinion rod (which has been produced by a drawing process giving the proper shape of teeth) ; and (3) the lantern pinion, in which two brass collets on the arbor carry into proper holes short steel wires as teeth.
A screw machine will produce from Boo to 1,5o0, and a pinion milling machine from 500 to 3,00o per day. In the lantern pinions the arbor of wire of proper size has pivots turned on it by an automatic screw machine at a rate of 2,000 to 3,00o per day. The collets will then produce from 3,00o to 5,000 partly finished pinions. These go from a hopper to an automatic drilling machine which drills through one collet and partially through another the circle of holes for the short wires at 3,00o to 5,000 per day.
Dials are punched from sheet brass, buffed, plated, wire-brushed and lacquered. The numerals are applied by a rubber roller taking ink from multiple electros and with this press two operators will produce from 5,000 to 8,000 dials per day. Hands made from steel or from nickel silver for holding luminous material, are progressively pierced for the centre hole, swaged for the socket and blanked in a press capable of producing over ioo,000 per day. The blueing is done in an appropriate furnace.