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One of the most remarkable advances in machine tools was due to the studies of Fred W. Taylor. He entered a large steel plant in 1880 and was immediately struck with the enormous waste of effort on the part of the men in the plant. There was at that time considerable dissatisfaction among the workmen, and when Taylor endeavored to speed up work he was faced by the incontrovertible argument that he had no idea how much work a certain machine ought to turn out. There was nothing for him to do but either back down or study machine tools and discover their maximum capacity. This led him to investigate the matter of cutting speeds. For years he spent all of his spare time studying this subject, timing machines and experimenting with different types of cutting tools. He estimated that in the twenty-six years of his investigation he converted 800,000 pounds of steel into chips. What he wished to discover was the best depth of cut, the best speed of cutting, and the best speed at which the tool should be fed into the work. He soon discovered that, contrary to prevailing opinion, the round-nosed tool was better than the diamond-pointed tool, that the coarse slow-cutting speed was better than a fine cut at high speed. He discovered that the best method of lubricating the tools was to keep them bathed in a heavy stream of water, supersaturated with carbonate of soda, so as to prevent the metal from rusting. The best tool steel of that day was known as a self-hardening steel. Manufacturers of the cutting steels had warned Taylor that he must not use water on these tools. Taylor, however, was not satisfied to take the word of others, but proceeded to investigate the matter himself, and discovered that he could safely increase the cutting speed of his tools 33 per cent by the use of a heavy stream of water for lubricating purposes. This led Taylor and his associate, Maunsel White, to investigate the different kinds of tool steels, and eventually they evolved a chrome tungsten tool which could do from two to four times the work of other tools. Later vanadium was added to the alloy, further improving the tool.

At the Exposition in Paris, in 1900, foreign manufacturers were astonished to find enormous lathes operating at high speed with the cutting tools taking such heavy cuts and feeding so fast that the nose of the tool was actually heated to a dull red heat, and yet it kept its cutting edge perfectly. This was a revelation to tool makers abroad, and it led immediately to the adoption of American high-speed cutting tools.

The development of the automobile, which began to take on serious proportions at about that time, is responsible above all other machines for improvements in American machine tools, and for the extension of the American system of interchangeable manufacture. When automobiles came to be made on the interchangeable system and in enormous quantities so that the cost was reduced to within the limits of the average man’s pocketbook, they began to make mechanics of men who before that had never used a tool; and this new and widespread interest in machinery stimulated the production of better and more efficient tools. Hence the progress of machine tools in the past few years has been simply phenomenal.