At this point and at this early day, therefore, was inaugurated the modern system of interchangeable manufacturing—or the manufacturing, in large numbers, of duplicate parts, within such a limited degree of variation as to admit of their ready interchangeability with one another. The system was not one that would be confined to the manufacture of arms, but was adaptable to the production of all kinds of small and moderate-sized machinery, and was the initial effort which in due time revolutionized the then existing shop methods, and which has since built up the American system of manufacturing to the proud distinction of being superior to anything of the kind in other manufacturing countries.
In the operations of modern manufacturing, the principal object sought is to turn out the product economically and accurately. To produce these results economically, the parts must be produced very rapidly. To produce them rapidly, not only must there be a very complete and efficient equipment of machines, attachments, tools, jigs, fixtures, and gauges or measuring devices, but there must also be a very complete system of shop methods by which the operation of this equipment is carried on.
It has been well said that "the man in whose brain the manufacturing system was born was he who first took a piece of scrap iron and drilled two holes in it, to guide a drill in making another piece with two holes in it the same distance apart as in the first piece." The men who now fill our drafting rooms and tool rooms, and who devise and construct tools for the production of interchangeable metal parts, are his descendants. They have made possible the manufacture of the breech-loading gun, the typewriter, the cheap sewing machine, the cash register, the machine-made watch, the automobile, as well as a thousand and one other mechanical articles, machines, and devices which form an integral part of our twentieth-century civilization.
To render these systems efficient and economical for these purposes, the work must be repetition or duplicate work. That is, there must be very large numbers of each of the different parts; and to carry out the scheme of operation for the division and subdivision of work; a single operation on a large number of parts is performed; then the work is handled again, perhaps in another machine, and another operation is performed; and so on until the part is complete. Thus a piece of comparatively simple form may require a large number of separate and distinct operations to complete it. But, as each single operation is performed by one operator, he may give his undivided attention to the accuracy of that operation; hence very accurate work can be produced.
A MACHINE SHOP WITH GALLERIES AT THE SHIPBUILDING PLANT OF THE GAS ENGINE & POWER CO. AND CHARLES L. SEABURY & CO., CONSOLIDATED
In the development of these systems, the work has continually grown more and more complex, as have also the requirements as to the buildings in which manufacturing work is performed, and as to the equipment necessary to perform it. Conditions have been continually changing; greater speed as well as greater accuracy in all machine operations has been demanded; and a largely increased output per employee has been required. So great and urgent has been this demand that the employee of to-day will turn out from three to ten times the volume of product of a given kind that he did only a few years ago. Undoubtedly this result has been brought about in great measure by the great improvement in machines, tools, and fixtures. Much is also due to the use of tools composed of high-speed steel; still more, to the employment of improved systems for handling work.
But all of these do not fully explain the enormous increase in product per employee. This has been brought about by various methods of shop management. One of these is the specialization of operations and the division and subdivision of departments, whereby each operator has a certain well-defined and very limited number of operations to perform. These operations he performs over and over, hundreds and sometimes thousands of times daily, until he becomes so accustomed to each movement that the operations are performed not only with great rapidity but also with great accuracy. Still another factor in the question of individual output, is the efforts that have been made through systems of premiums, bonus, and similar methods of reward for individual effort when the output reaches or exceeds a certain fixed limit. These rewards are not confined to the operatives, but are often extended to the foremen, assistant foremen, gang bosses, and others of the "non-productive" force who have indirectly contributed to the efficiency of individuals and hence to departmental efficiency.