Principles and Design of Precision Gauges

Abstract

IN these days of motor-cars, electric fittings and so on, everyone learns something of the value of interchangeability of parts and also experiences the disadvantage of finding that a part ‘will not fit’. The progress of manufacture, indeed, depends largely on parts being interchangeable, and in mass production it is absolutely necessary to place limits on the permissible variation from standard dimensions. This necessity has given rise to the system of working to gauges, a system which received a great impetus through the manufacture of vast quantities of munitions during the War, and which to-day is perhaps used most extensively in the manufacture of motor-car engines and other parts. From being a comparative novelty, gauging has become a matter of ordinary routine, while the making and testing of gauges has itself become an industry. There will thus be many persons who will be able to appreciate the pamphlet of Mr. R. J. Foster on “The Principle and Design of Precision Gauges for Interchange-ability” recently issued by the Association of Engineering and Ship-building Draughtsmen, and published by the Draughtsman Publishing Co., Ltd. (2s.). In this the reader will find sections on tolerances and fits and limits, plug gauges, pin gauges, external and internal gauges, height and depth gauges and comparators, together with many sketches and useful notes.