CIRCULAR RUNOUT

DEFINITION

Runout is a composite tolerance used to control the functional relationship of one or more features of a part to a datum axis. The types of features controlled by runout tolerance include those surfaces constructed around a datum axis and those constructed at right angles to a datum axis.

TOLERANCE ZONE

Each considered feature must be within its runout tolerance when the part is rotated about the datum axis. The tolerance specified for a controlled surface is the total tolerance or full indicator movement (FIM).

REFERENCE TO DATUMS

One or more datum features. Relation to more than one datum feature is specified to stabilize the tolerance zone in more then one direction.

APPLICABILITY OF MMC, LMC, RFS TO FEATURE

The specified tolerance can only apply on an RFS basis.

APPLICABILITY OF MMC, LMC, RFS TO DATUMS

The specified datum can only apply on an RFS basis.

TYPICAL USE

Typically used to control circularity and concentricity simultaneously.



NOTES :

  1. Circular runout provides control of circular elements of a surface. The tolerance is applied independently at each circular measuring position as the part is rotated 360.

  2. Where applied to surface constructed at right angles to the datum axis, circular runout controls circular elements of a plane surface (wobble).



SEE ALSO