1. Based on the ASME Y14.5M- 1994 Dimensioning and Tolerancing Standard DIMENSIONAL ENGINEERING

2. INTRODUCTION Geometric dimensioning and tolerancing (GD&T) is an international engineering language that is used on engineering drawings (blue prints) to describe product in three dimensions. GD&T uses a series of internationally recognized symbols rather than words to describe the product. These symbols are applied to the features of a part and provide a very concise and clear definition of design intent. GD&T is a very precise mathematical language that describes the form, orientation and location of part features in zones of tolerance. These zones of tolerance are then described relative to a Cartesian coordinate system. ASME Y14.5M-1994 American national Standards Institute/American Society of Mechanical Engineers

3. Tolerances of Form Straightness Flatness Circularity Cylindricity (ASME Y14.5M-1994, 6.4.1) (ASME Y14.5M-1994, 6.4.3) (ASME Y14.5M-1994, 6.4.2) (ASME Y14.5M-1994, 6.4.4)

4. Extreme Variations of Form Allowed By Size Tolerance 25.1 25 25 (MMC) 25.1 (LMC) 25 (MMC) 25.1 (LMC) MMC Perfect Form Boundary Internal Feature of Size

5. Extreme Variations of Form Allowed By Size Tolerance 25 24.9 25 (MMC) 24.9 (LMC) MMC Perfect Form Boundary 25 (MMC) 24.9 (LMC) External Feature of Size

6. 25 +/-0.25 0.1 Tolerance 0.5 Tolerance Straightness is the condition where an element of a surface or an axis is a straight line Straightness (Flat Surfaces) 0.5 0.1

7. Straightness (Flat Surfaces) 24.75 min 25.25 max 0.5 Tolerance Zone 0.1 Tolerance Zone The straightness tolerance is applied in the view where the elements to be controlled are represented by a straight line In this example each line element of the surface must lie within a tolerance zone defined by two parallel lines separated by the specified tolerance value applied to each view. All points on the surface must lie within the limits of size and the applicable straightness limit.

8. Straightness (Surface Elements) MMC 0.1 Tolerance Zone 0.1 MMC 0.1 Tolerance Zone MMC 0.1 Tolerance Zone In this example each longitudinal element of the surface must lie within a tolerance zone defined by two parallel lines separated by the specified tolerance value. The feature must be within the limits of size and the boundary of perfect form at MMC. Any barreling or waisting of the feature must not exceed the size limits of the feature.

9. Straightness (RFS) 0.1 Outer Boundary (Max) MMC 0.1 Diameter Tolerance Zone Outer Boundary = Actual Feature Size + Straightness Tolerance In this example the derived median line of the feature’s actual local size must lie within a tolerance zone defined by a cylinder whose diameter is equal to the specified tolerance value regardless of the feature size. Each circular element of the feature must be within the specified limits of size. However, the boundary of perfect form at MMC can be violated up to the maximum outer boundary or virtual condition diameter.

10. Straightness (MMC) 15 14.85 15.1 Virtual Condition 15 (MMC) 0.1 Diameter Tolerance Zone 15.1 Virtual Condition 14.85 (LMC) 0.25 Diameter Tolerance Zone Virtual Condition = MMC Feature Size + Straightness Tolerance In this example the derived median line of the feature’s actual local size must lie within a tolerance zone defined by a cylinder whose diameter is equal to the specified tolerance value at MMC. As each circular element of the feature departs from MMC, the diameter of the tolerance cylinder is allowed to increase by an amount equal to the departure from the local MMC size. Each circular element of the feature must be within the specified limits of size. However, the boundary of perfect form at MMC can be violated up to the virtual condition diameter. 0.1 M

11. Flatness Flatness is the condition of a surface having all elements in one plane. Flatness must fall within the limits of size. The flatness tolerance must be less than the size tolerance. 25 +/-0.25 24.75 min 25.25 max 0.1 0.1 Tolerance Zone In this example the entire surface must lie within a tolerance zone defined by two parallel planes separated by the specified tolerance value. All points on the surface must lie within the limits of size and the flatness limit.

12. Circularity is the condition of a surface where all points of the surface intersected by any plane perpendicular to a common axis are equidistant from that axis. The circularity tolerance must be less than the size tolerance 90 0.1 0.1 Wide Tolerance Zone Circularity (Roundness) In this example each circular element of the surface must lie within a tolerance zone defined by two concentric circles separated by the specified tolerance value. All points on the surface must lie within the limits of size and the circularity limit. 0.1

13. Cylindricity Cylindricity is the condition of a surface of revolution in which all points are equidistant from a common axis. Cylindricity is a composite control of form which includes circularity (roundness), straightness, and taper of a cylindrical feature. 0.1 Tolerance Zone MMC 0.1 In this example the entire surface must lie within a tolerance zone defined by two concentric cylinders separated by the specified tolerance value. All points on the surface must lie within the limits of size and the cylindricity limit.

14. ____________ and ___________ are individual line or circular element (2-D) controls. Form Control Quiz The four form controls are ____________, ________, ___________, and ____________. Rule #1 states that unless otherwise specified a feature of size must have ____________ at MMC. ________ and ____________ are surface (3-D) controls. Circularity can be applied to both ________ and _______ cylindrical parts. 1. 2. 3. 4. 5. Form controls require a datum reference. Form controls do not directly control a feature’s size. A feature’s form tolerance must be less than it’s size tolerance. Flatness controls the orientation of a feature. Size limits implicitly control a feature’s form. 6. 7. 8. 9. 10. Questions #1-5 Fill in blanks (choose from below) straightness flatness circularity cylindricity perfect form straight tapered profile true position angularity Answer questions #6-10 True or False

15. Tolerances of Orientation Angularity Perpendicularity Parallelism (ASME Y14.5M-1994,6.6.2) (ASME Y14.5M-1994,6.6.4) (ASME Y14.5M-1994,6.6.3)

16. Angularity (Feature Surface to Datum Surface) Angularity is the condition of the planar feature surface at a specified angle (other than 90 degrees) to the datum reference plane, within the specified tolerance zone. A 20 +/-0.5 30 o A 19.5 min 0.3 Wide Tolerance Zone 30 o A 20.5 max 0.3 Wide Tolerance Zone 30 o The tolerance zone in this example is defined by two parallel planes oriented at the specified angle to the datum reference plane. 0.3A

17. Angularity is the condition of the feature axis at a specified angle (other than 90 degrees) to the datum reference plane, within the specified tolerance zone. A 0.3 A A 60 o The tolerance zone in this example is defined by a cylinder equal to the length of the feature, oriented at the specified angle to the datum reference plane. 0.3 Circular Tolerance Zone Angularity (Feature Axis to Datum Surface) NOTE: Tolerance applies to feature at RFS

18. 0.3 Circular Tolerance Zone NOTE: Tolerance applies to feature at RFS Angularity is the condition of the feature axis at a specified angle (other than 90 degrees) to the datum reference axis, within the specified tolerance zone. 0.3 Circular Tolerance Zone A Datum Axis A Angularity (Feature Axis to Datum Axis) The tolerance zone in this example is defined by a cylinder equal to the length of the feature, oriented at the specified angle to the datum reference axis. NOTE: Feature axis must lie within tolerance zone cylinder 0.3A o 45

19. 0.3 A A 0.3 Wide Tolerance Zone AA Perpendicularity is the condition of the planar feature surface at a right angle to the datum reference plane, within the specified tolerance zone. Perpendicularity (Feature Surface to Datum Surface) 0.3 Wide Tolerance Zone The tolerance zone in this example is defined by two parallel planes oriented perpendicular to the datum reference plane.

20. C Perpendicularity is the condition of the feature axis at a right angle to the datum reference plane, within the specified tolerance zone. Perpendicularity (Feature Axis to Datum Surface) 0.3 C 0.3 Circular Tolerance Zone 0.3 Diameter Tolerance Zone 0.3 Circular Tolerance Zone NOTE: Tolerance applies to feature at RFS The tolerance zone in this example is defined by a cylinder equal to the length of the feature, oriented perpendicular to the datum reference plane.

21. Perpendicularity (Feature Axis to Datum Axis) NOTE: Tolerance applies to feature at RFS The tolerance zone in this example is defined by two parallel planes oriented perpendicular to the datum reference axis. Perpendicularity is the condition of the feature axis at a right angle to the datum reference axis, within the specified tolerance zone. 0.3 Wide Tolerance Zone A Datum Axis A 0.3 A

22. A A 25 +/-0.5 25.5 max 0.3 Wide Tolerance Zone A 24.5 min 0.3 Wide Tolerance Zone A Parallelism is the condition of the planar feature surface equidistant at all points from the datum reference plane, within the specified tolerance zone. Parallelism (Feature Surface to Datum Surface) The tolerance zone in this example is defined by two parallel planes oriented parallel to the datum reference plane.

23. A 0.3 Wide Tolerance Zone Parallelism (Feature Axis to Datum Surface) 0.3 A A NOTE: The specified tolerance does not apply to the orientation of the feature axis in this direction Parallelism is the condition of the feature axis equidistant along its length from the datum reference plane, within the specified tolerance zone. The tolerance zone in this example is defined by two parallel planes oriented parallel to the datum reference plane. NOTE: Tolerance applies to feature at RFS

24. A B Parallelism (Feature Axis to Datum Surfaces) A B 0.3 Circular Tolerance Zone Parallelism is the condition of the feature axis equidistant along its length from the two datum reference planes, within the specified tolerance zone. The tolerance zone in this example is defined by a cylinder equal to the length of the feature, oriented parallel to the datum reference planes. NOTE: Tolerance applies to feature at RFS 0.3 A B

25. Parallelism (Feature Axis to Datum Axis) Parallelism is the condition of the feature axis equidistant along its length from the datum reference axis, within the specified tolerance zone. A 0.1 A 0.1 Circular Tolerance Zone Datum Axis A The tolerance zone in this example is defined by a cylinder equal to the length of the feature, oriented parallel to the datum reference axis. NOTE: Tolerance applies to feature at RFS

26. Orientation Control Quiz The three orientation controls are __________, ___________, and ________________. 1. 2. 3. 4. 5. A _______________ is always required when applying any of the orientation controls. ________________ is the appropriate geometric tolerance when controlling the orientation of a feature at right angles to a datum reference. Orientation tolerances indirectly control a feature’s form. Mathematically all three orientation tolerances are _________. Orientation tolerances do not control the ________ of a feature. 6. Orientation tolerance zones can be cylindrical. Parallelism tolerances do not apply to features of size. To apply an angularity tolerance the desired angle must be indicated as a basic dimension. 7. 8. 9. 10. To apply a perpendicularity tolerance the desired angle must be indicated as a basic dimension. Questions #1-5 Fill in blanks (choose from below) angularity perpendicularity parallelism datum reference identical location profile datum feature datum target Answer questions #6-10 True or False

27. Tolerances of Runout Circular Runout (ASME Y14.5M-1994, 6.7.1.2.1) Total Runout (ASME Y14.5M-1994,6.7.1.2.2)

28. Datum feature Datum axis (established from datum feature Angled surfaces constructed around a datum axis External surfaces constructed around a datum axis Internal surfaces constructed around a datum axis Surfaces constructed perpendicular to a datum axis Features Applicable to Runout Tolerancing

29. 0 + - Full Indicator Movement MaximumMinimum Total Tolerance Maximum Reading Minimum Reading Full Part Rotation Measuring position #1 (circular element #1) Circular Runout When measuring circular runout, the indicator must be reset to zero at each measuring position along the feature surface. Each individual circular element of the surface is independently allowed the full specified tolerance. In this example, circular runout can be used to detect 2- dimensional wobble (orientation) and waviness (form), but not 3-dimensional characteristics such as surface profile (overall form) or surface wobble (overall orientation). Measuring position #2 (circular element #2) Circular runout can only be applied on an RFS basis and cannot be modified to MMC or LMC.

30. o 360 Part Rotation 50 +/- 2 o o As Shown on Drawing Means This: Datum axis A Single circular element Circular Runout (Angled Surface to Datum Axis) 0.75A A 50 +/-0.25 0 + - NOTE: Circular runout in this example only controls the 2-dimensional circular elements (circularity and coaxiality) of the angled feature surface not the entire angled feature surface Full Indicator Movement ( ) The tolerance zone for any individual circular element is equal to the total allowable movement of a dial indicator fixed in a position normal to the true geometric shape of the feature surface when the part is rotated 360 degrees about the datum axis. The tolerance limit is applied independently to each individual measuring position along the feature surface. Allowable indicator reading = 0.75 max. When measuring circular runout, the indicator must be reset when repositioned along the feature surface. Collet or Chuck

31. As Shown on Drawing 50 +/-0.25 0.75A Circular Runout (Surface Perpendicular to Datum Axis) o 360 Part Rotation 0 + - Datum axis A Single circular element NOTE: Circular runout in this example will only control variation in the 2-dimensional circular elements of the planar surface (wobble and waviness) not the entire feature surface The tolerance zone for any individual circular element is equal to the total allowable movement of a dial indicator fixed in a position normal to the true geometric shape of the feature surface when the part is rotated 360 degrees about the datum axis. The tolerance limit is applied independently to each individual measuring position along the feature surface. Means This: Allowable indicator reading = 0.75 max. When measuring circular runout, the indicator must be reset when repositioned along the feature surface. A

32. 0 + - Allowable indicator reading = 0.75 max. Single circular element o 360 Part Rotation Means This: As Shown on Drawing 50 +/-0.25 0.75A Datum axis A When measuring circular runout, the indicator must be reset when repositioned along the feature surface. Circular Runout (Surface Coaxial to Datum Axis) The tolerance zone for any individual circular element is equal to the total allowable movement of a dial indicator fixed in a position normal to the true geometric shape of the feature surface when the part is rotated 360 degrees about the datum axis. The tolerance limit is applied independently to each individual measuring position along the feature surface. NOTE: Circular runout in this example will only control variation in the 2-dimensional circular elements of the surface (circularity and coaxiality) not the entire feature surface A

33. 0 + - Allowable indicator reading = 0.75 max. Single circular element o 360 Part Rotation Means This: As Shown on Drawing 0.75A-B Datum axis A-B When measuring circular runout, the indicator must be reset when repositioned along the feature surface. Circular Runout (Surface Coaxial to Datum Axis) The tolerance zone for any individual circular element is equal to the total allowable movement of a dial indicator fixed in a position normal to the true geometric shape of the feature surface when the part is rotated 360 degrees about the datum axis. The tolerance limit is applied independently to each individual measuring position along the feature surface. NOTE: Circular runout in this example will only control variation in the 2-dimensional circular elements of the surface (circularity and coaxiality) not the entire feature surface Machine center B A

34. As Shown on Drawing 50 +/-0.25 Circular Runout (Surface Related to Datum Surface and Axis) o 360 Part Rotation 0 + - Datum axis B Single circular element The tolerance zone for any individual circular element is equal to the total allowable movement of a dial indicator fixed in a position normal to the true geometric shape of the feature surface when the part is located against the datum surface and rotated 360 degrees about the datum axis. The tolerance limit is applied independently to each individual measuring position along the feature surface. Means This: A Allowable indicator reading = 0.75 max. When measuring circular runout, the indicator must be reset when repositioned along the feature surface. Collet or Chuck Stop collar 0.75A B Datum plane A B

35. 0 + Full Indicator Movement Total Tolerance Maximum Reading Minimum Reading Full Part Rotation - 0 + - Total Runout Maximum Minimum When measuring total runout, the indicator is moved in a straight line along the feature surface while the part is rotated about the datum axis. It is also acceptable to measure total runout by evaluating an appropriate number of individual circular elements along the surface while the part is rotated about the datum axis. Because the tolerance value is applied to the entire surface, the indicator must not be reset to zero when moved to each measuring position. In this example, total runout can be used to measure surface profile (overall form) and surface wobble (overall orientation). Indicator Path Total runout can only be applied on an RFS basis and cannot be modified to MMC or LMC.

36. Full Part Rotation 50 +/- 2 o o As Shown on Drawing A 50 +/-0.25 0.75A Means This: Datum axis A 0 + - The tolerance zone for the entire angled surface is equal to the total allowable movement of a dial indicator positioned normal to the true geometric shape of the feature surface when the part is rotated about the datum axis and the indicator is moved along the entire length of the feature surface. 0 + - NOTE: Unlike circular runout, the use of total runout will provide 3-dimensional composite control of the cumulative variations of circularity, coaxiality, angularity, taper and profile of the angled surface Total Runout (Angled Surface to Datum Axis) Collet or Chuck When measuring total runout, the indicator must not be reset when repositioned along the feature surface. (applies to the entire feature surface) Allowable indicator reading = 0.75 max.

37. 0 + - Total Runout (Surface Perpendicular to Datum Axis) As Shown on Drawing A 50 +/-0.25 0.75A 35 10 0 + - Datum axis A Full Part Rotation 35 10 Means This: NOTE: The use of total runout in this example will provide composite control of the cumulative variations of perpendicularity (wobble) and flatness (concavity or convexity) of the feature surface. The tolerance zone for the portion of the feature surface indicated is equal to the total allowable movement of a dial indicator positioned normal to the true geometric shape of the feature surface when the part is rotated about the datum axis and the indicator is moved along the portion of the feature surface within the area described by the basic dimensions. When measuring total runout, the indicator must not be reset when repositioned along the feature surface. (applies to portion of feature surface indicated) Allowable indicator reading = 0.75 max.

38. Runout Control Quiz Answer questions #1-12 True or False Total runout is a 2-dimensional control. 1. Runout tolerances are used on rotating parts. Total runout tolerances should be applied at MMC. Runout tolerances can be applied to surfaces at right angles to the datum reference. 2. 3. 4. 5. Circular runout tolerances apply to single elements. 6. Circular runout tolerances are used to control an entire feature surface. Runout tolerances always require a datum reference. 7. Circular runout and total runout both control axis to surface relationships. 8. Circular runout can be applied to control taper of a part. 9. Total runout tolerances are an appropriate way to limit “wobble” of a rotating surface. 10. Runout tolerances are used to control a feature’s size. 11. Total runout can control circularity, straightness, taper, coaxiality, angularity and any other surface variation. 12.

39. Tolerances of Profile Profile of a Line Profile of a Surface (ASME Y14.5M-1994, 6.5.2b) (ASME Y14.5M-1994, 6.5.2a)

40. 18 Max Profile of a Line 2 Wide Size Tolerance Zone 1 A B C A 17 +/- 1 1 Wide Profile Tolerance Zone C A1 20 X 20 A2 20 X 20 A3 20 X 20 B The profile tolerance zone in this example is defined by two parallel lines oriented with respect to the datum reference frame. The profile tolerance zone is free to float within the larger size tolerance and applies only to the form and orientation of any individual line element along the entire surface. Profile of a Line is a two-dimensional tolerance that can be applied to a part feature in situations where the control of the entire feature surface as a single entity is not required or desired. The tolerance applies to the line element of the surface at each individual cross section indicated on the drawing. 16 Min.

41. Profile of a Surface is a three-dimensional tolerance that can be applied to a part feature in situations where the control of the entire feature surface as a single entity is desired. The tolerance applies to the entire surface and can be used to control size, location, form and/or orientation of a feature surface. Profile of a Surface 2 Wide Tolerance Zone Size, Form and Orientation A A1 20 X 20 A2 20 X 20 A3 20 X 20 C 2 A B C 23.5 Nominal Location The profile tolerance zone in this example is defined by two parallel planes oriented with respect to the datum reference frame. The profile tolerance zone is located and aligned in a way that enables the part surface to vary equally about the true profile of the feature. B

42. Profile of a Surface A1 20 X 20 A2 20 X 20 A3 20 X 20 B C 50 B C 1 Wide Total Tolerance Zone (Bilateral Tolerance) The tolerance zone in this example is defined by two parallel planes oriented with respect to the datum reference frame. The profile tolerance zone is located and aligned in a way that enables the part surface to vary equally about the true profile of the trim. 1 A B C Nominal Location 0.5 Inboard 0.5 Outboard Profile of a Surface when applied to trim edges of sheet metal parts will control the location, form and orientation of the entire trimmed surface. When a bilateral value is specified, the tolerance zone allows the trim edge variation and/or locational error to be on both sides of the true profile. The tolerance applies to the entire edge surface.

43. Profile of a Surface A1 20 X 20 A2 20 X 20 A3 20 X 20 B C 50 B C 0.5 Wide Total Tolerance Zone (Unilateral Tolerance) Profile of a Surface when applied to trim edges of sheet metal parts will control the location, form and orientation of the entire trimmed surface. When a unilateral value is specified, the tolerance zone limits the trim edge variation and/or locational error to one side of the true profile. The tolerance applies to the entire edge surface. The tolerance zone in this example is defined by two parallel planes oriented with respect to the datum reference frame. The profile tolerance zone is located and aligned in a way that allows the trim surface to vary from the true profile only in the inboard direction. 0.5 A B C Nominal Location

44. Profile of a Surface A1 20 X 20 A2 20 X 20 A3 20 X 20 B C 50 1.2 A B C B C 50 0.5 Inboard 0.7 Outboard 1.2 Wide Total Tolerance Zone (Unequal Bilateral Tolerance) Profile of a Surface when applied to trim edges of sheet metal parts will control the location, form and orientation of the entire trimmed surface. Typically when unequal values are specified, the tolerance zone will represent the actual measured trim edge variation and/or locational error. The tolerance applies to the entire edge surface. The tolerance zone in this example is defined by two parallel planes oriented with respect to the datum reference frame. The profile tolerance zone is located and aligned in a way that enables the part surface to vary from the true profile more in one direction (outboard) than in the other (inboard). 0.5 Nominal Location

45. A 25 A 0.5 0.1 25.25 24.75 0.1 Wide Tolerance Zone A Composite Profile of Two Coplanar Surfaces w/o Orientation Refinement Profile of a Surface Form Only Location & Orientation

46. 0.1 Wide Tolerance Zone 25.25 24.75 A A A 25 A 0.5 A 0.1 Form & Orientation Composite Profile of Two Coplanar Surfaces With Orientation Refinement Profile of a Surface Location

47. 6. Profile Control Quiz Profile tolerances always require a datum reference. Answer questions #1-13 True or False 1. Profile of a surface tolerance is a 2-dimensional control. Profile of a line tolerances should be applied at MMC. Profile tolerances can be applied to features of size. 2. 3. 4. 5. Profile of a surface tolerance should be used to control trim edges on sheet metal parts. Profile tolerances can be combined with other geometric controls such as flatness to control a feature. Profile of a line tolerances apply to an entire surface. 7. Profile of a line controls apply to individual line elements. 8. Profile tolerances only control the location of a surface. 9. Composite profile controls should be avoided because they are more restrictive and very difficult to check. 10. Profile tolerances can be applied either bilateral or unilateral to a feature. 11. Profile tolerances can be applied in both freestate and restrained datum conditions. 12. Tolerances shown in the lower segment of a composite profile feature control frame control the location of a feature to the specified datums. 13.

48. In composite profile applications, the tolerance shown in the upper segment of the feature control frame applies only to the ________ of the feature. Profile Control Quiz The two types of profile tolerances are _________________, and ____________________. 1. 2. 3. 4. 5. Profile tolerances can be used to control the ________, ____, ___________, and sometimes size of a feature. Profile tolerances can be applied _________ or __________. _________________ tolerances are 2-dimensional controls. ____________________ tolerances are 3-dimensional controls. Questions #1-9 Fill in blanks (choose from below) 6. _________________ can be used when different tolerances are required for location and form and/or orientation. 7. When using profile tolerances to control the location and/or orientation of a feature, a _______________ must be included in the feature control frame. 8. When using profile tolerances to control form only, a ______ __________ is not required in the feature control frame. 9. profile of a linedatum reference composite profilebilateral locationform primary datum true geometric counterpart orientationprofile of a surface unilateral virtual condition

49. Tolerances of Location True Position Concentricity Symmetry (ASME Y14.5M-1994, 5.2) (ASME Y14.5M-1994, 5.12) (ASME Y14.5M-1994, 5.13)

50. Notes

51. 10.25 +/- 0.5 8.5 +/- 0.1 Rectangular Tolerance Zone 10.25 8.5 +/- 0.1 Circular Tolerance Zone B A C Coordinate vs Geometric Tolerancing Methods Coordinate Dimensioning Geometric Dimensioning Rectangular Tolerance ZoneCircular Tolerance Zone 1.4 +/- 0.5 57% Larger Tolerance Zone Circular Tolerance Zone Rectangular Tolerance Zone Increased Effective Tolerance 1.4 A B C

52. Formula to determine the actual radial position of a feature using measured coordinate values (RFS) Z positional tolerance /2 X 2 Y 2 + Z = X = 2 Y = 2 X Y Z Feature axis actual location (measured) Positional tolerance zone cylinder Feature axis true position (designed) Positional Tolerance Verification Z =total radial deviation “X” measured deviation “Y” measured deviation Actual feature boundary (Applies when a circular tolerance is indicated)

53. Formula to determine the actual radial position of a feature using measured coordinate values (MMC) Z X 2 Y 2 + Z = X = 2 Y = 2 X Y Z Feature axis actual location (measured) Positional tolerance zone cylinder Feature axis true position (designed) Positional Tolerance Verification Z =total radial deviation “X” measured deviation “Y” measured deviation Actual feature boundary +( actual - MMC) 2 = positional tolerance (Applies when a circular tolerance is indicated)

54. Bi-directional True Position Rectangular Coordinate Method 35 10 A C B 1.5 A B C 0.5 A B C 2X 10 35 1.5 Wide Tolerance Zone 0.5 Wide Tolerance Zone True Position Related to Datum Reference Frame 10 B C Each axis must lie within the 1.5 X 0.5 rectangular tolerance zone basically located to the datum reference frame As Shown on Drawing Means This: 2X 6 +/-0.25

55. Bi-directional True Position Multiple Single-Segment Method 35 10 A C B 35 1.5 Wide Tolerance Zone 0.5 Wide Tolerance Zone True Position Related to Datum Reference Frame 10 B C Each axis must lie within the 1.5 X 0.5 rectangular tolerance zone basically located to the datum reference frame As Shown on Drawing Means This: 2X 6 +/-0.25 1.5 A B C 0.5 A B

56. 35 10 A C B As Shown on Drawing Means This: 1.5 A B C 0.5 A B C BOUNDARY 10 35 10 B C 2X 13 +/-0.25 2X 6 +/-0.25 12.75 MMC width of slot -1.50 Position tolerance 11.25 Maximum boundary Both holes must be within the size limits and no portion of their surfaces may lie within the area described by the 11.25 x 5.25 maximum boundaries when the part is positioned with respect to the datum reference frame. The boundary concept can only be applied on an MMC basis. o 90 True position boundary related to datum reference frame A Bi-directional True Position Noncylndrical Features (Boundary Concept) M M 5.75 MMC length of slot -0.50 Position tolerance 5.25 maximum boundary

57. Composite True Position Without Pattern Orientation Control 35 10 A C B 35 True Position Related to Datum Reference Frame 10 B C Each axis must lie within each tolerance zone simultaneously As Shown on Drawing Means This: 2X 6 +/-0.25 1.5 A B C 0.5 A 0.5 Feature-Relating Tolerance Zone Cylinder 1.5 Pattern-Locating Tolerance Zone Cylinder pattern location relative to Datums A, B, and C pattern orientation relative to Datum A only (perpendicularity)

58. Composite True Position With Pattern Orientation Control 35 10 A C B 35 True Position Related to Datum Reference Frame 10 B C Each axis must lie within each tolerance zone simultaneously As Shown on Drawing Means This: 2X 6 +/-0.25 0.5 Feature-Relating Tolerance Zone Cylinder 1.5 Pattern-Locating Tolerance Zone Cylinder pattern location relative to Datums A, B, and C pattern orientation relative to Datums A and B 1.5 A B C 0.5 A B

59. Location (Concentricity) Datum Features at RFS A 15.95 15.90 As Shown on Drawing Derived Median Points of Diametrically Opposed Elements Axis of Datum Feature A Means This: Within the limits of size and regardless of feature size, all median points of diametrically opposed elements must lie within a 0.5 cylindrical tolerance zone. The axis of the tolerance zone coincides with the axis of datum feature A. Concentricity can only be applied on an RFS basis. 0.5 A 6.35 +/- 0.05 0.5 Coaxial Tolerance Zone

60. Location (Symmetry) Datum Features at RFS A 15.95 15.90 0.5 A 6.35 +/- 0.05 Derived Median Points Center Plane of Datum Feature A 0.5 Wide Tolerance Zone Means This: Within the limits of size and regardless of feature size, all median points of opposed elements must lie between two parallel planes equally disposed about datum plane A, 0.5 apart. Symmetry can only be applied on an RFS basis. As Shown on Drawing

61. True Position Quiz Answer questions #1-11 True or False Positional tolerances are applied to individual or patterns of features of size. 1. Cylindrical tolerance zones more closely represent the functional requirements of a pattern of clearance holes. True position tolerances can control a feature’s size. Positional tolerances are applied on an MMC, LMC, or RFS basis. 2. 3. 4. 5. True position tolerance values are used to calculate the minimum size of a feature required for assembly. 6. Composite true position tolerances should be avoided because it is overly restrictive and difficult to check. Composite true position tolerances can only be applied to patterns of related features. 7. The tolerance value shown in the upper segment of a composite true position feature control frame applies to the location of a pattern of features to the specified datums. 8. Positional tolerances can be used to control circularity 9. 10. 11. The tolerance value shown in the lower segment of a composite true position feature control frame applies to the location of a pattern of features to the specified datums. True position tolerances can be used to control center distance relationships between features of size.

62. Positional tolerance zones can be ___________, ___________, or spherical 1. 2. 3. 4. 5. ________________ are used to establish the true (theoretically exact) position of a feature from specified datums. Positional tolerancing is a _____________ control. Positional tolerance can apply to the ____ or ________________ of a feature. _____ and ________ fastener equations are used to determine appropriate clearance hole sizes for mating details 6. 7. _________ tolerance zones are recommended to prevent fastener interference in mating details. 8. projected3-dimensional surface boundaryfloating locationfixed basic dimensions maximum material cylindricalpattern-locatingrectangular feature-relating True Position Quiz Questions #1-9 Fill in blanks (choose from below) The tolerance shown in the upper segment of a composite true position feature control frame is called the ________________ tolerance zone. The tolerance shown in the lower segment of a composite true position feature control frame is called the ________________ tolerance zone. 9. Functional gaging principles can be applied when __________ ________ condition is specified axis

63. Notes

65. Fixed and Floating Fastener Exercises

66. 2x M10 X 1.5 (Reference) B A ?.? 2x 10.50 +/- 0.25 M Calculate Required Positional Tolerance 0.5 2x ??.?? +/- 0.25 M Calculate Nominal Size A B T = H - F H = Minimum Hole Size = 10.25 F = Max. Fastener Size = 10 T = 10.25 -10 T = ______ Floating Fasteners H = F +T F = Max. Fastener Size = 10 T = Positional Tolerance = 0.50 H = 10 + 0.50 H = ______ In applications where two or more mating details are assembled, and all parts have clearance holes for the fasteners, the floating fastener formula shown below can be used to calculate the appropriate hole sizes or positional tolerance requirements to ensure assembly. The formula will provide a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+T or T=H-F General Equation Applies to Each Part Individually remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value.

67. 2x M10 X 1.5 (Reference) B A 0.25 2x 10.50 +/- 0.25 M 0.5 2x 10.75 +/- 0.25 M A B Floating Fasteners REMEMBER!!! All Calculations Apply at MMC H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+T or T=H-F General Equation Applies to Each Part Individually T = H - F H = Minimum Hole Size = 10.25 F = Max. Fastener Size = 10 T = 10.25 -10 T = 0.25 Calculate Required Positional Tolerance F = Max. Fastener Size = 10 T = Positional Tolerance = 0.5 H = 10 +.5 H = 10.5 Minimum H = F +T In applications where two or more mating details are assembled, and all parts have clearance holes for the fasteners, the floating fastener formula shown below can be used to calculate the appropriate hole sizes or positional tolerance requirements to ensure assembly. The formula will provide a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value. Calculate Nominal Size

68. F = Max. Fastener Size = 10.00 T = Positional Tolerance = 0.80 2x M10 X 1.5 (Reference) B A 0.8 2x ??.?? +/- 0.25 M Calculate Required Clearance Hole Size. 2X M10 X 1.5 A B Fixed Fasteners H = 10.00 + 2(0.8) H = _____ H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+2T or T=(H-F)/2 General Equation Used When Positional Tolerances Are Equal In fixed fastener applications where two mating details have equal positional tolerances, the fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size and/or positional tolerance required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note that in this example the positional tolerances indicated are the same for both parts.) 0.8 M 10 P APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED Nominal Size (MMC For Calculations) H = F + 2T remember: the size tolerance must be added to the calculated MMC size to obtain the correct nominal value. 10

69. 2x M10 X 1.5 (Reference) B A 2x 11.85 +/- 0.25 0.8 M Calculate Required Clearance Hole Size. A B In fixed fastener applications where two mating details have equal positional tolerances, the fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size and/or positional tolerance required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note that in this example the positional tolerances indicated are the same for both parts.) Fixed Fasteners H = F + 2T F = Max. Fastener Size = 10.00 T = Positional Tolerance = 0.80 H = 10.00 + 2(0.8) H = 11.60 Minimum H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+2T or T=(H-F)/2 General Equation Used When Positional Tolerances Are Equal 0.8 M 10 P APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED 2X M10 X 1.5 Nominal Size (MMC For Calculations) remember: the size tolerance must be added to the calculated MMC size to obtain the correct nominal value. REMEMBER!!! All Calculations Apply at MMC 10

70. 2x M10 X 1.5 (Reference) B A 2x 11.85 +/- 0.25 0.8 M Calculate Required Clearance Hole Size. A B In fixed fastener applications where two mating details have equal positional tolerances, the fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size and/or positional tolerance required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note that in this example the positional tolerances indicated are the same for both parts.) Fixed Fasteners H = F + 2T F = Max. Fastener Size = 10 T = Positional Tolerance = 0.8 H = 10 + 2(0.8) H = 11.6 Minimum H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+2T or T=(H-F)/2 General Equation Used When Positional Tolerances Are Equal 0.8 M 10 P APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED 2X M10 X 1.5 Nominal Size (MMC For Calculations) remember: the size tolerance must be added to the calculated MMC size to obtain the correct nominal value. REMEMBER!!! All Calculations Apply at MMC 10

71. 2x M10 X 1.5 (Reference) B A 0.5 2x 11.25 +/- 0.25 M Calculate Required Positional Tolerance. (Both Parts) A B In applications where two mating details are assembled, and one part has restrained fasteners, the fixed fastener formula shown below can be used to calculate appropriate hole sizes and/or positional tolerances required to ensure assembly. The formula will provide a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note: in this example the resultant positional tolerance is applied to both parts equally.) Fixed Fasteners T = (H - F)/2 H = Minimum Hole Size = 11 F = Max. Fastener Size = 10 T = (11 - 10)/2 T = 0.50 H= Min. diameter of clearance hole F= Maximum diameter of fastener T= Positional tolerance diameter H=F+2T or T=(H-F)/2 General Equation Used When Positional Tolerances Are Equal 2X M10 X 1.5 0.5 M 10 P APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED Nominal Size (MMC For Calculations) REMEMBER!!! All Calculations Apply at MMC 10

72. 2x M10 X 1.5 (Reference) B A 0.5 2x ??.?? +/- 0.25 M Calculate Required Clearance Hole Size. A B Fixed Fasteners H = Min. diameter of clearance hole F = Maximum diameter of fastener T 1 = Positional tolerance (Part A) T 2 = Positional tolerance (Part B) H=F+(T 1 + T 2 ) General Equation Used When Positional Tolerances Are Not Equal F = Max. Fastener Size = 10 T 1 = Positional Tol. (A) = 0.50 T 2 = Positional Tol. (B) = 1 H = 10+ (0.5 + 1) H = ____ H=F+(T 1 + T 2 ) In fixed fastener applications where two mating details have unequal positional tolerances, the fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size and/or positional tolerances required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note that in this example the positional tolerances indicated are not equal.) APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED 2X M10 X 1.5 Nominal Size (MMC For Calculations) remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value. 10 1 M P

73. 2x M10 X 1.5 (Reference) B A 0.5 2x 11.75 +/- 0.25 M Calculate Required Clearance Hole Size. A B In fixed fastener applications where two mating details have unequal positional tolerances, the fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size and/or positional tolerances required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at their extreme of positional tolerance. (Note that in this example the positional tolerances indicated are not equal.) Fixed Fasteners F = Max. Fastener Size = 10 T 1 = Positional Tol. (A) = 0.5 T 2 = Positional Tol. (B) = 1 H = 10 + (0.5 + 1) H = 11.5 Minimum APPLIES WHEN A PROJECTED TOLERANCE ZONE IS USED H = Min. diameter of clearance hole F = Maximum diameter of fastener T 1 = Positional tolerance (Part A) T 2 = Positional tolerance (Part B) H= F+(T 1 + T 2 ) General Equation Used When Positional Tolerances Are Not Equal H=F+(T 1 + T 2 ) 1 M 10 P 2X M10 X 1.5 Nominal Size (MMC For Calculations) remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value. REMEMBER!!! All Calculations Apply at MMC 10

74. D P HF A B APPLIES WHEN A PROJECTED TOLERANCE ZONE IS NOT USED 2x 10.05 +/-0.05 B A 0.5 M 2x ??.?? +/-0.25 Calculate Nominal Size 0.5 M In applications where a projected tolerance zone is not indicated, it is necessary to select a positional tolerance and minimum clearance hole size combination that will allow for any out-of-squareness of the feature containing the fastener. The modified fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at the extreme positional tolerance. Fixed Fasteners H = 10.00 + 0.5 + 0.5(1 + 2(15/20)) H = __________ H= F + T 1 + T 2 (1+(2P/D)) remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value. H= Min. diameter of clearance hole F= Maximum diameter of pin T 1 = Positional tolerance (Part A) T 2 = Positional tolerance (Part B) D= Min. depth of pin (Part A) P= Maximum projection of pin F = Max. pin size = 10 T 1 = Positional Tol. (A) = 0.5 T 2 = Positional Tol. (B) = 0.5 D = Min. pin depth = 20. P = Max. pin projection = 15

75. D P HF A B H= Min. diameter of clearance hole F= Maximum diameter of pin T 1 = Positional tolerance (Part A) T 2 = Positional tolerance (Part B) D= Min. depth of pin (Part A) P= Maximum projection of pin APPLIES WHEN A PROJECTED TOLERANCE ZONE IS NOT USED 2x 10.05 +/-0.05 B A 0.5 M 2x 12 +/-0.25 Calculate Nominal Size 0.5 M F = Max. pin size = 10 T 1 = Positional tol. (A) = 0.5 T 2 = Positional tol. (B) = 0.5 D = Min. pin depth = 20 P = Max. pin projection = 15 H= F + T 1 + T 2 (1+(2P/D)) H = 10 + 0.5 + 0.5(1 + 2(15/20)) H = 11.75 Minimum In applications where a projected tolerance zone is not indicated, it is necessary to select a positional tolerance and minimum clearance hole size combination that will allow for any out-of-squareness of the feature containing the fastener. The modified fixed fastener formula shown below can be used to calculate the appropriate minimum clearance hole size required to ensure assembly. The formula provides a “zero-interference” fit when the features are at MMC and at the extreme positional tolerance. Fixed Fasteners H= F + T 1 + T 2 (1+(2P/D)) REMEMBER!!! All Calculations Apply at MMC remember: the size tolerance must be added to the calculated MMC hole size to obtain the correct nominal value.

76. Answers to Quizzes and Exercises

77. Rules and Definitions Quiz 1. Tight tolerances ensure high quality and performance. 2. The use of GD&T improves productivity. 3. Size tolerances control both orientation and position. 4. Unless otherwise specified size tolerances control form. 5. A material modifier symbol is not required for RFS. 6. A material modifier symbol is not required for MMC. 7. Title block default tolerances apply to basic dimensions. 8. A surface on a part is considered a feature. 9. Bilateral tolerances allow variation in two directions. 10. A free state modifier can only be applied to a tolerance. 11. A free state datum modifier applies to “assists” & “rests”. 12. Virtual condition applies regardless of feature size. FALSE TRUE FALSE TRUE FALSE TRUE FALSE Questions #1-12 True or False

78. Material Condition Quiz Internal Features MMC LMC External Features MMC LMC.890.885.895.890 23.45 +0.05/-0.25 10.75 +0.25/-0 123. 5 +/-0.1 23.45 +0.05/-0.25 10.75 +0/-0.25 123. 5 +/-0.1 Calculate appropriate values Fill in blanks 10.75 11 23.2 23.5 123.4 123.6.890.895 10.75 10.5 23.5 23.2 123.6 123.4.890.885

79. 1. Datum target areas are theoretically exact. 2. Datum features are imaginary. 3. Primary datums have only three points of contact. 4. The 6 Degrees of Freedom are U/D, F/A, & C/C. 5. Datum simulators are part of the gage or tool. 6. Datum simulators are used to represent datums. 8. All datum features must be dimensionally stable. 9. Datum planes constrain degrees of freedom. 10. Tertiary datums are not always required. 12. Datums should represent functional features. Datum Quiz 11. All tooling locators (CD’s) are used as datums. Questions #1-12 True or False 7. Datums are actual part features. FALSE TRUE FALSE TRUE FALSE TRUE

80. Datum Quiz The three planes that make up a basic datum reference frame are called primary, secondary, and tertiary. An unrestrained part will exhibit 3-linear and 3-rotational degrees of freedom. A planar primary datum plane will restrain 1-linear and 2-rotational degrees of freedom. The primary and secondary datum planes together will restrain five degrees of freedom. The primary, secondary and tertiary datum planes together will restrain all six degrees of freedom. The purpose of a datum reference frame is to restrain movement of a part in a gage or tool. A datum must be functional, repeatable, and coordinated. A datum feature is an actual feature on a part. A datum is a theoretically exact point, axis or plane. A datum simulator is a precise surface used to establish a simulated datum. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Questions #1-10 Fill in blanks (choose from below) primary secondary tertiary3-rotational 3-linear 2-rotational datum three two one six functional restrain movementcoordinated datum simulator datum feature repeatable five 1-linear

81. Straightness and circularity are individual line or circular element (2-D) controls. Form Control Quiz The four form controls are straightness, flatness, circularity, and cylindricity. Rule #1 states that unless otherwise specified a feature of size must have perfect form at MMC. Flatness and cylindricity are surface (3-D) controls. Circularity can be applied to both straight and tapered cylindrical parts. 1. 2. 3. 4. 5. Form controls require a datum reference. Form controls do not directly control a feature’s size. A feature’s form tolerance must be less than it’s size tolerance. Flatness controls the orientation of a feature. Size limits implicitly control a feature’s form. 6. 7. 8. 9. 10. FALSE TRUE FALSE Answer questions #6-10 True or False Questions #1-5 Fill in blanks (choose from below) straightness flatness circularity cylindricity perfect form straight tapered profile true position angularity

82. Orientation Control Quiz The three orientation controls are angularity, parallelism, and perpendicularity. 1. 2. 3. 4. 5. A datum reference is always required when applying any of the orientation controls. Perpendicularity is the appropriate geometric tolerance when controlling the orientation of a feature at right angles to a datum reference. Orientation tolerances indirectly control a feature’s form. Mathematically all three orientation tolerances are identical. Orientation tolerances do not control the location of a feature. Answer questions #6-10 True or False 6. TRUE Orientation tolerance zones can be cylindrical. Parallelism tolerances do not apply to features of size. To apply an angularity tolerance the desired angle must be indicated as a basic dimension. 7. 8. 9. 10. TRUE FALSE TRUE To apply a perpendicularity tolerance the desired angle must be indicated as a basic dimension. Questions #1-5 Fill in blanks (choose from below) angularity perpendicularity parallelism datum reference identical location profile datum feature datum target

83. Runout Control Quiz Answer questions #1-12 True or False TRUE Total runout is a 2-dimensional control. 1. Runout tolerances are used on rotating parts. Total runout tolerances should be applied at MMC. Runout tolerances can be applied to surfaces at right angles to the datum reference. 2. 3. 4. 5. FALSE Circular runout tolerances apply to single elements. FALSE TRUE 6. Circular runout tolerances are used to control an entire feature surface. Runout tolerances always require a datum reference. 7. Circular runout and total runout both control axis to surface relationships. 8. TRUE Circular runout can be applied to control taper of a part. 9. FALSE Total runout tolerances are an appropriate way to limit “wobble” of a rotating surface. 10. Runout tolerances are used to control a feature’s size. 11. Total runout can control circularity, straightness, taper, coaxiality, angularity and any other surface variation. 12. TRUE FALSE TRUE FALSE

84. In composite profile applications, the tolerance shown in the upper segment of the feature control frame applies only to the location of the feature. Profile Control Quiz The two types of profile tolerances are profile of a line, and profile of a surface. 1. 2. 3. 4. 5. Profile tolerances can be used to control the location, form, orientation, and sometimes size of a feature. Profile tolerances can be applied bilateral or unilateral. Profile of a line tolerances are 2-dimensional controls. Profile of a surface tolerances are 3-dimensional controls. Questions #1-9 Fill in blanks (choose from below) 6. Composite Profile can be used when different tolerances are required for location and form and/or orientation. 7. When using profile tolerances to control the location and/or orientation of a feature, a datum reference must be included in the feature control frame. 8. When using profile tolerances to control form only, a datum reference is not required in the feature control frame. 9. profile of a linedatum reference composite profilebilateral locationform primary datum true geometric counterpart orientationprofile of a surface unilateral virtual condition

85. 6. Profile Control Quiz Profile tolerances always require a datum reference. Answer questions #1-13 True or False 1. Profile of a surface tolerance is a 2-dimensional control. Profile of a line tolerances should be applied at MMC. Profile tolerances can be applied to features of size. 2. 3. 4. 5. Profile of a surface tolerance should be used to control trim edges on sheet metal parts. Profile tolerances can be combined with other geometric controls such as flatness to control a feature. Profile of a line tolerances apply to an entire surface. 7. Profile of a line controls apply to individual line elements. 8. Profile tolerances only control the location of a surface. 9. Composite profile controls should be avoided because they are more restrictive and very difficult to check. 10. Profile tolerances can be applied either bilateral or unilateral to a feature. 11. Profile tolerances can be applied in both freestate and restrained datum conditions. 12. Tolerances shown in the lower segment of a composite profile feature control frame control the location of a feature to the specified datums. 13. TRUE FALSE TRUE FALSE TRUE FALSE

86. True Position Quiz Answer questions #1-11 True or False TRUE Positional tolerances are applied to individual or patterns of features of size. 1. Cylindrical tolerance zones more closely represent the functional requirements of a pattern of clearance holes. True position tolerances can control a feature’s size. Positional tolerances are applied on an MMC, LMC, or RFS basis. 2. 3. 4. 5. FALSE True position tolerance values are used to calculate the minimum size of a feature required for assembly. TRUE 6. Composite true position tolerances should be avoided because it is overly restrictive and difficult to check. Composite true position tolerances can only be applied to patterns of related features. 7. The tolerance value shown in the upper segment of a composite true position feature control frame applies to the location of a pattern of features to the specified datums. 8. TRUE Positional tolerances can be used to control circularity 9. FALSE 10. 11. TRUE FALSE TRUE FALSE TRUE The tolerance value shown in the lower segment of a composite true position feature control frame applies to the location of a pattern of features to the specified datums. True position tolerances can be used to control center distance relationships between features of size.

87. Positional tolerance zones can be rectangular, cylindrical, or spherical 1. 2. 3. 4. 5. Basic dimensions are used to establish the true (theoretically exact) position of a feature from specified datums. Positional tolerancing is a 3-dimensional control. Positional tolerance can apply to the axis or surface boundary of a feature. Fixed and floating fastener equations are used to determine appropriate clearance hole sizes for mating details 6. 7. Projected tolerance zones are recommended to prevent fastener interference in mating details. 8. projected3-dimensional surface boundaryfloating locationfixed basic dimensions maximum material cylindricalpattern-locatingrectangular feature-relating True Position Quiz Questions #1-9 Fill in blanks (choose from below) The tolerance shown in the upper segment of a composite true position feature control frame is called the pattern-locating tolerance zone. The tolerance shown in the lower segment of a composite true position feature control frame is called the feature-relating tolerance zone. 9. Functional gaging principles can be applied when maximum material condition is specified axis

88. ENDEND

89. Notes

92. Extreme Variations of Form Allowed By Size Tolerance 25.1 25 25 24.9 25 (MMC) 25.1 (LMC) 25 (MMC) 24.9 (LMC) 25 (MMC) 25.1 (LMC) MMC Perfect Form Boundary 25 (MMC) 24.9 (LMC)

93. Virtual and Resultant Condition Boundaries Internal and External Features (MMC Concept)

94. Virtual Condition Boundary Internal Feature (MMC Concept) 12.5 Virtual Condition Boundary 13.5 MMC Size of Feature 1 Applicable Geometric Tolerance Calculating Virtual Condition 1 A B C M 14 +/- 0.5 C B XX.X A As Shown on Drawing Axis Location of MMC Hole Shown at Extreme Limit Boundary of MMC Hole Shown at Extreme Limit 1 Positional Tolerance Zone at MMC True (Basic) Position of Hole True (Basic) Position of Hole Other Possible Extreme Locations Virtual Condition Inner Boundary Maximum Inscribed Diameter ()

95. Resultant Condition Boundary Internal Feature (MMC Concept) 1 A B C M 14 +/- 0.5 C B XX.X A 16.5 Resultant Condition Boundary 14.5 LMC Size of Feature 2 Geometric Tolerance (at LMC) Calculating Resultant Condition (Internal Feature) As Shown on Drawing Axis Location of LMC Hole Shown at Extreme Limit Boundary of LMC Hole Shown at Extreme Limit 2 Positional Tolerance Zone at LMC True (Basic) Position of Hole True (Basic) Position of Hole Other Possible Extreme Locations Resultant Condition Outer Boundary Minimum Circumscribed Diameter ()

96. Virtual Condition Boundary External Feature (MMC Concept) 15.5 Virtual Condition Boundary 14.5 MMC Size of Feature 1 Applicable Geometric Tolerance Calculating Virtual Condition 1 A B C M 14 +/- 0.5 C B XX.X XX.XX A As Shown on Drawing Axis Location of MMC Feature Shown at Extreme Limit Boundary of MMC Feature Shown at Extreme Limit 1 Positional Tolerance Zone at MMC True (Basic) Position of Feature True (Basic) Position of Feature Other Possible Extreme Locations Virtual Condition Outer Boundary Minimum Circumscribed Diameter ()

97. Resultant Condition Boundary External Feature (MMC Concept) 1 A B C M 14 +/- 0.5 C B XX.X A 11.5 Resultant Condition Boundary 13.5 LMC Size of Feature 2 Geometric Tolerance (at LMC) Calculating Resultant Condition (External Feature) As Shown on Drawing Axis Location of LMC Feature Shown at Extreme Limit Boundary of LMC feature Shown at Extreme Limit 2 Positional Tolerance Zone at LMC True (Basic) Position of Feature True (Basic) Position of Feature Other Possible Extreme Locations Resultant Condition Inner Boundary Maximum Inscribed Diameter ()

98. 3X 5.0  5mm is 3 times repeated. A space is used after X Maximum Material Condition (MMC): The condition where the feature contains the maximum material within the stated limits of size – for example, the largest pin or the smallest hole. Least Material Condition (LMC): The condition where the feature contains the least material with in the stated limits of size - for example, the smallest pin or largest hole.

99. GEOMETRIC CHARACTERISTIC SYMBOLS FOR INDIVIDUAL FEATURES TYPE OF TOLERANCE CHARACTERISTICSYMBOL FORM STRAIGHNESS FLATNESS CIRCULARITY (ROUNDNESS) CYLINDRICITY FOR INDIVIDUAL OR RELATED FEATURES FROFILE PROFILE OF A SURFACE PROFILE OF A LINE FOR RELATED FEATURES ORIENTATION ANGULARITY PERPENDICULARITY PARALLELISM LOCATION POSITION CONCENTRICITY SYMMETRY RUNOUT CIRCULAR RUNOUT TOTAL RUNOUT