Your Source for GD&T Training and Materials Back to GD&T Tips Runout vs Coaxiality (Concentricity) When in Doubt Use Runout! Avoid specifying concentricity. Concentricity requires deriving the median line of a feature. All of the features shown below are concentric. Usually, designs require that a feature be round as well as concentric like example A. A better geometric control is usually circular runout. Circular runout controls circularity (roundness) as well as concentricity. Back to GD&T Tips Home GD&T
