circularity callout<\/a>?<\/p>\nThe circularity callout does check the circularity of a feature, but it does not do so in reference to a datum axis.<\/p>\n
So, a surface that is perfectly round would meet the circularity callout even if it is off-centred. This could, however, cause the part to wobble when it rotates during service.<\/p>\n
Circular products that require close tolerances or rotate at high speeds must rotate around the central axis besides being as circular as possible to prevent errors in operation. Even a small wobble can significantly affect the functionality and reduce service life.<\/p>\n
Circular runout helps us control and measure this wobble to ensure it is within permissible limits.<\/p>\n
The datum axis acts as an anchor for the tolerance zone in circular runout. The callout creates a 2D circular tolerance zone around the specified datum axis. The ideal surface of the feature lies in this tolerance zone. In order to meet this callout, all points on the actual surface must lie in this zone.<\/p>\n
Runout manages to specify everything necessary to avoid the wobbling effect without putting many different and too tight tolerances<\/strong> on the part.<\/p>\nFeature Control Frame of Circular Runout<\/h2>\n
<\/p>\n
The feature control frame follows the same rules as it does with other GD&T symbols. The circular runout frame consists of three sections.<\/p>\n
Circular Runout Symbol<\/h3>\n