Page:The Cycle Industry (1921).djvu/60

46 number of front forks and handle-bars, to name only two parts, are available when they are wanted. Without their aid chaos would reign, and there might be 1,000 bicycles ready for delivery in a given week and no handle-bars forthcoming at the last moment. Such has been known to occur in factories where the organization is weak.

In a very large factory, where everything is made on the premises, the directors arrange for a production of, say, 1,000 machines a week for six months. The requisitions for material go through the buying department, the designs go from the drawing office and in a reasonable time, if the organization is complete, the parts commence to collect in the various stores throughout the factory. When the stock is sufficiently forward to ensure a regular supply to the various shops; the stores begin to issue the orders to build and assemble, paint and finish, and so the process goes on.

The production of bicycles in very large quantities has brought about a difference in some of the processes of making such parts as frame lugs, handle-bar lugs, fork crowns, crank brackets, fork ends, etc. What are known as pressings are largely replacing stampings and castings. The latter are made in one pair of dies from red-hot steel by stamping the plastic metal into the die or moulding red-hot iron in a mould made of compressed sand; the pressings are formed from sheet steel between dies, but the metal is treated cold and usually has to pass through more than one pair of dies before it assumes the desired shape.

The multiplicity of dies is necessary to allow the cold sheet metal to be gradually formed; if it were attempted to bend it suddenly to a sharp radius, it would break or spring back, so the sheet is coaxed, so to speak, to assume the form desired.