What is a radius gauge?
A radius gauge is a hand-held tool which has many precision rounded curves (radii) machined into its edges.
A radius gauge may also be referred to as a fillet gauge.
Radius gauges are available as small steel inserts joined with a mounted design (gauge sets), or as loose single gauges of which there are many varieties.
The single gauge pictured has five measuring surfaces and is often stored in a case or wallet.
What is meant by radius?
A radius is the term used to describe a rounded form, specifically a corner or rounded edge.
This is the part of an object that is measured, or the shape which can be drawn with the use of a radius gauge.
Either a concave or convex radius can be measured with a radius gauge.
A concave radius curves inward.
A convex radius curves outward.
Radius gauges are used to check concave and convex profiles by pressing the gauge against the desired object.
The gauge acts as a reference with its precisely machined radius mated (placed as close as possible) against the radius in question.
They can clarify with no gap between surfaces that a radius is identical to the measurement shown on the gauge.
What is an internal and external radius?
Radius gauges are required to measure objects which include rounded internal or external edges as part of their design. This requires the tool to have internal (concave) and external (convex) measuring capability.
How are radius gauges different from other gauges?
Radius gauges are different from other gauges because they are available with various cut outs (projections) machined into their edges at different locations for best fit.
They are available as sets or as individual blades.