A new set of optimum angle gauges has been designed which consists of 13 pieces. Angles from 3" to 110° 11' 10" can be realised in 169118 discrete values (to cover the range 3" to 109° 13' 46" in 3" (sometimes 2" or 1") steps). Within this range at most eight gauges need to be combined for any given angle reducing errors when compared with a set of the NPL Combination Angle Gauges (13 pieces set made by the Coventry Gauge and Tool Co Ltd) which requires up to 13 gauges to cover the range 3" to 81° 40' 57" in 3" steps (98019 values). Tables are given for the combination of gauges required to obtain a particular discrete angle within the range.
Anon. 1979. Handbook of Measurement. Heilong-jiang Administrative Office of Standard Weights and Measures, Harbin University of Industry. Science Publishing House, Peking, PR of China, p 393.
2.
Knoyle, C.H.1950. 'N.P.L. Combination Angle Gauges. Methods of Production and Size Generation' (Communication from the National Physical Laboratory), Machinery, 31 August.
