Geometric Dimensioning Reference Chart

Jul 6, 2011 at 1:25 pm in Reference, Standards by admin


Type of tolerance Geometric characteristics Symbol Can be applied to a feature? Can be applied to a feature of size? Can affect virtual condition? Datum reference used? Can useGd&t maximummaterialcondition.pngmodifier? Can useGd&t regardlessoffeaturesize.pngmodifier? Can be affected by a bonus tolerance? Can be affected by a shift tolerance?
Form Straightness Gd&t straightness.png Yes Yes Yes
(note 1)		 No Yes
(note 1)		 No
(note 5)		 Yes
(note 4)		 No
Form Flatness Gd&t flatness.png Yes No No No No No
(note 5)		 No No
Form Circularity Gd&t circularity.png Yes No No No No No
(note 5)		 No No
Form Cylindricity Gd&t cylindricity.png Yes No No No No No
(note 5)		 No No
Profile Profile of a line Gd&t profileline.png Yes No No Yes
(note 2)		 No No
(note 5)		 No Yes
(note 3)
Profile Profile of a surface Gd&t profile.png Yes No No Yes
(note 2)		 No No
(note 5)		 No Yes
(note 3)
Orientation Perpendicularity Gd&t perpendicularity.png Yes Yes Yes
(note 1)		 Yes Yes
(note 1)		 No
(note 5)		 Yes
(note 4)		 Yes
(note 3)
Orientation Angularity Gd&t angularity.png Yes Yes Yes
(note 1)		 Yes Yes
(note 1)		 No
(note 5)		 Yes
(note 4)		 Yes
(note 3)
Orientation Parallelism Gd&t parallelism.png Yes Yes Yes
(note 1)		 Yes Yes
(note 1)		 No
(note 5)		 Yes
(note 4)		 Yes
(note 3)
Location Symmetry Gd&t symmetry.png  ?
(note 6)		  ?
(note 6)		  ?
(note 6)		  ?
(note 6)		  ?
(note 6)		  ?
(note 6)		  ?
(note 6)		  ?
(note 6)
Location Positional tolerance Gd&t position.png No Yes Yes Yes Yes Yes Yes
(note 4)		 Yes
(note 3)
Location Concentricity Gd&t concentricity.png No Yes Yes Yes No No
(note 5)		 No No
Runout Circular runout Gd&t runout.png Yes Yes Yes
(note 1)		 Yes No No
(note 5)		 No No
Runout Total runout Gd&t totalrunout.png Yes Yes Yes
(note 1)		 Yes No No
(note 5)		 No No

Notes:

  1. When applied to a feature-of-size
  2. Can also be used as a form control without a datum reference
  3. When a datum feature-of-size is referenced with the MMC modifier
  4. When an MMC modifier is used
  5. Automatic per rule #3
  6. The symmetry symbol’s characteristics were not included in the version of the chart that this chart is derived from. The symmetry symbol was dropped from the Y14.5M standard around 1988 and re-added around 1994. (It’s been speculated that it will be re-dropped the next time the standard is revised.)
Symbol↓ Modifier↓
Gd&t freestate.png Free state
Gd&t leastmaterialcondition.png Least material condition (LMC)
Gd&t maximummaterialcondition.png Maximum material condition (MMC)
Gd&t projectedtolerancezone.png Projected tolerance zone
Gd&t regardlessoffeaturesize.png Regardless of feature size (RFS) (note 1)
Gd&t tangentplane.png Tangent plane
Gd&t unilateral.png Unilateral (note 2)

Notes:

  1. The Gd&t regardlessoffeaturesize.png symbol is not part of the 1994 version. See para. A5, bullet 3. Also para. D3. Also, Figure 3-8.
  2. The Gd&t unilateral.png symbol is not part of the 1994 version. It is in “Y14.41-” and may appear in a future version of Y14.5. It refers to unequal profile distribution.
  3. All the symbols above are used in a feature control frame to specify a feature’s description, tolerance, modifier and datum references.