10 Runout

Describe the two types of runout tolerances. Complete an interpretation drawing showing how each of the runout tolerances is measured. Apply both types of runout tolerances on circular features and face surfaces. Specify runout tolerances using multiple (compound) datum feature references. Limit the area of application for a runout tolerance. © Goodheart-Willcox Co., Inc.

Runout Surface variation relative to axis of rotation Tolerances define amount of variation permitted Circular and total © Goodheart-Willcox Co., Inc.

Circular Runout Single element measured by dial indicator in a fixed position while part rotates Each measurement of multiple elements evaluated separately Largest reading is the circular runout for the part © Goodheart-Willcox Co., Inc.

Feature Control Frame © Goodheart-Willcox Co., Inc.

Multiple Datum Features © Goodheart-Willcox Co., Inc.

Primary and Secondary © Goodheart-Willcox Co., Inc.

Circular Runout Applications Cylinders Cones Spherical surfaces Flat surfaces Any surface with circular cross section centered on an axis © Goodheart-Willcox Co., Inc.

Circular Runout—Cylinder Multiple, but separate readings per feature Surface control relative to axis of rotation May be internal, such as holes © Goodheart-Willcox Co., Inc.

Circular Runout—Conical Surface © Goodheart-Willcox Co., Inc.

Circular Runout— Spherical Surface © Goodheart-Willcox Co., Inc.

Circular Runout—Flat Surface © Goodheart-Willcox Co., Inc.

Datum Axis All runout tolerances must include at least one datum feature reference to establish axis Datum feature may be entire surface or datum targets © Goodheart-Willcox Co., Inc.

Multiple Datum Features Also known as compound datum features Two features establish one datum Identified by two letters separated by a hyphen Functional features are preferred Coaxial holes may be used © Goodheart-Willcox Co., Inc.

Limited Tolerance Zone Application © Goodheart-Willcox Co., Inc.

Primary Axis, Secondary Plane © Goodheart-Willcox Co., Inc.

Total Runout All elements on surface evaluated together Variations measured relative to axis Symbol is double arrows Diameter symbol never used © Goodheart-Willcox Co., Inc.

Total Runout—Cylinder Total of all variation per feature Surface control relative to axis of rotation May be internal, such as holes © Goodheart-Willcox Co., Inc.

Total Runout—Face Surfaces Applied on extension lines Connected with leader Dial indicator moves perpendicular to axis © Goodheart-Willcox Co., Inc.

Combined Effects of Size and Runout Runout may be larger than size tolerance Size tolerance may be larger than runout Runout may occur on perfect form feature © Goodheart-Willcox Co., Inc.

Multiple datum features Circular runout Surface variation measured relative to an axis of rotation at a circular cross section. Multiple datum features Two or more datum features that act together to establish a single datum plane or axis. Commonly called a compound datum feature. © Goodheart-Willcox Co., Inc.

Runout Variation of a surface relative to an axis of rotation. Total runout The amount of variation measured across an entire surface when the part is rotated on an axis of rotation. © Goodheart-Willcox Co., Inc.