1. Orientation Tolerances7
Orientation Tolerances

2. Identify, apply, and interpret orientation tolerances.
Complete orientation tolerance specifications including one or two datum feature references.
Explain the effects of material condition modifiers when orientation tolerances are applied to features of size.
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3. Calculate the virtual condition for internal and external features of size to which an orientation tolerance is applied.
Complete tolerance specifications that include orientation and form requirements on a single feature.
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4. Orientation Tolerances
Orientation tolerances specify the allowable parallelism, perpendicularity, or angularity variation of a feature relative to one or more datums.
They are specified using a feature control frame, and may be applied to surfaces and to features of size.
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5. Orientation Tolerance Categories
Parallelism
Perpendicularity
Angularity
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6. Orientation Tolerance Symbols
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7. Feature Control Frames
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8. Virtual Condition
MMC applied to feature of size establishes a virtual condition
Virtual conditions of mating parts are equal or provide a clearance
Internal features
Vc = MMC – orientation tolerance
External features
Vc = MMC + orientation tolerance
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9. Feature Center Plane and Feature Axis
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10. Parallelism Interpretation—Surface
Orientation between flat surface and datum plane may be specified with parallelism tolerance
Size tolerance between parallel flat surfaces establishes orientation
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11. Parallelism Interpretation—Cylinder
Orientation between feature axis and datum plane or datum axis may be specified with parallelism tolerance
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12. Perpendicularity on a Surface
90° dimension not required
Tolerance must be specified
Feature control frame on extension line or leader to the surface
Must reference a datum
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13. Face Surface Elements on a Shaft
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14. Perpendicularity Applied to Features of Size
Establishes control of the axis or center plane of the feature, or may be defined as control within the virtual condition
Feature control frame must be associated with the size dimension
May be adjacent to dimension
May be attached to dimension line
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15. Perpendicularity of a Hole—Axis Interpretation
Must be controlled relative to a datum feature
The perpendicularity tolerance value is diameter of a cylindrical zone
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16. Controlling Perpendicularity of a Center Plane—Drawing
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17. Controlling Perpendicularity of a Center Plane–Possible Condition #1
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18. Controlling Perpendicularity of a Center Plane—Nonparallel Sides
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19. Angularity on Surfaces
Tolerances always referenced to one or more datums
Feature control frame attached to leader or extension line
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20. Tangent Plane
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21. Combined Form and Orientation Tolerances
Control orientation to one value and form to a smaller value
Orientation also controls form when applied to a surface
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