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An Encyclopedia of the History of Technology part 44. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART TWO POWER AND ENGINEERING instruments but the method was first used for production in 1835 by Joseph Whitworth using a worm cutter as a hob to make spiral gears. Several other patents were obtained for hobbing machines but the first fully geared example to be used was that made by George B.Grant c. 1887. By the end of the nineteenth century the general machine tools were established in their operating principles and many refinements had been made in machine spindle and carriage drives by gearing systems such as the gearbox invented in 1891 by W.P.Norton and incorporated in Hendey-Norton lathes. The features of interchangeable manufacture were well known and the mass production machinery ready for the explosion in manufacturing which was to take place in the twentieth century with the proliferation of the motor car and aeroplane. TWENTIETH-CENTURY ORGANIZATION OF PRODUCTION The key to further expansion lay in increasing the speed of cutting by machine tools and in organizing production to balance the machining and assembly of components so as to achieve the maximum rate of production of the completed product. Frederick W.Taylor was influential in both aspects. He carried out experiments on the shape cutting angles lubrication and materials of cutting tools to establish optimum efficiency and made dramatic improvements in output and tool life culminating in his development of High Speed Steel containing tungsten. He demonstrated it at the Paris Exhibition of 1900 cutting mild steel at 36.5m 120 feet per minute with the cutting tool red hot and this revelation was so fundamental that all types of machine tool were to need redesign to increase rigidity speed range and power to take advantage of the new tool material. The introduction of Stellite a chromium cobalt tungsten alloy in 1917 carbides by Krupps of Essen in 1926 and ceramic tools were to have similar effects later. A comparison of cutting speeds possible with these tool materials for grey cast iron shows
