Radius gauge

A radius gauge, also known as a fillet gauge,^[1] is a tool used to measure the radius of an object.^[2]

Radius gauges require a bright light behind the object to be measured. The gauge is placed against the edge to be checked and any light leakage between the blade and edge indicates a mismatch that requires correction.^[3]

A good set of gauges will offer both convex and concave sections, and allow for their application in awkward locations.

Every leaf has a different radius, for example with radius intervals of 0.25 mm or 0.5 mm.^[4] The material of the leaves is stainless steel. Each gauge is one of two types; either internal or external, which are used to check the radius of inner and outer surfaces, respectively.

• Thread pitch gauge
• Spherometer, an instrument for the precise measurement of radiuses

• Frane, James T. (1994), Craftsman's Illustrated Dictionary of Construction Terms (Illustrated ed.), Craftsman Book Company, ISBN 978-1-57218-008-6.
• Kennedy, Clifford W.; Hoffman, Edward G.; Bond, Steven D. (1987), Inspection and Gaging (6th, Illustrated ed.), Industrial Press Inc., ISBN 978-0-8311-1149-6.