The measuring tolerance of the ORG 3600 is +/- .5% for all measurements. In most cases, this is only suitable as a reference measurement. The ORG 3600 is NOT recognized by any (ISO) International Standards Organizations. There is NO calibration certificate for the ORG 3600. All gauges are tested and adjusted to a tolerance of better than +/- .5% on all measurements before they leave the shop.
The minimum chord (distance between outer contact points) needed for the ORG 3600 to take a measurement is 14″(356mm).
Arc Master Radius Gauges should be used for REFERENCE only. They are NOT registered with any Industry Standards Organization.
IMPORTANT: What you should do when you first receive your radius gauge.
To ensure proper calibration of your radius gauge, we recommend that at first use, check the gauge on a sample arc and record the measurement. This sample arc should have a radius of 100” or larger. The larger the radius sample your gauge is checked on, the more accurate the check. Make a note of the radius measurement on the sample arc and refer to this sample arc for all your regular radius checks.’