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Diameter reckoner
Page 78
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NOW AVAILABLE in the UK, a range of American-made periphery tapes—known as Pi-Tapes—give a fast, accurate method of measuring diameters. When wrapped round the circumference of a cylindrical component, the true diameter is read by Vernier scale to an accuracy of 0.001in.
Pi-Tapes are made from selected spring steel, 0.010in. thick with gradations and numerals engraved and acid etched on to a ground surface. The manufacturer states that each tape is checked on master gauge blanks to an accuracy of 0.001in. under standard conditions.
A comprehensive range of standard sizes is available, the smallest covering a diameter range of 0.8in. to 6in., the largest for diameters between 132in. and 144in. Longer or special-purpose tapes can be made to suit individual requirements.
Marketed by: A. P. Warren Ltd., 37 Sheen Road, Richmond, Surrey.