Dial Caliper Radius Gauge

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This is a precision tool that attaches to the end of a dial caliper with depth gauge, enabling users to measure radii with exactness. Reverse engineering a corner filet is one example of its application. Different sizes might be necessary, but this particular adapter measures 30mm wide. A smaller version would be required for measuring smaller objects. To use it: Attach the item to the bottom of the caliper. Place the assembly on a flat surface and lower the depth gauge until it rests on the surface. This will align it with the points on the tool, which form an arc length. Zero out your caliper dial (digital calipers work best) and press the depth gauge and adapter against a radius. Note how far the caliper's depth gauge travels upward back into the caliper. This distance represents the arc height. Visit this URL to input the numbers for calculating circle radius or diameter: https://dev000.mmdeveloper.tech/publicApps/radiusFromArc.html Alternatively, use the formula: L = Arc length (distance between points touching the radius) S = Sagitta (height of arc between center of points and center of radius 'corner') Radius = ((S ^ 2) + ((L / 2) ^ 2)) / (2 * S) I've encountered inconsistent results with this formula, so use it cautiously.