Key Points
Total runout is a 3D surface to axis control. It creates one tolerance zone that all surface elements must lie within simultaneously. When applied to a cylindrical feature, the tolerance zone is the radial separation between two cylinders coaxial with the datum axis. This controls 3D form (cylindricity), orientation and location to the datum axis. It does not control size, and therefore requires a separate size tolerance.
Example Drawing
Size tolerance controls size and form (per rule#1) within 0.4.
Total runout controls orientation, location, and refines cylindricity within 0.1.
How to Read It
Sample Inspection
Datum feature A is mounted in a collet or vee block. A dial indicator is placed on the surface at various locations along its length. At each location, the part is rotated a full revolution about the datum axis. The full indicator movement (FIM) shall be no more than 0.1. Although the specification requires all cross-sections to be within tolerance, a quality plan should define the number of places to be verified.