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Geometric Boundaries III , Interpretation and Application of GD&T

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Geometric Boundaries III, Interpretation and Application of GD&T per. ASME Y14.5-2009 and ASME Y14.41-2012

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Open: Geometric Boundaries III, Interpretation and Application of GD&T per. ASME Y14.5-2009 and ASME Y14.41-2012

Written and Illustrated by Kelly L. Bramble, FAA Airframe and Powerplant, ASME GDTP-S


1.2 Preface
1.3 Acknowledgments
1.4 Table of Contents
1.12 Introduction
1.13 Engineering Drawing Standards First and Third Angle Projection
1.14 Standards Based on ISO or ASME Standards
1.16 Corporate Standards
1.17 How the Geometric Dimensioning and Tolerancing System Works
1.18 Tolerances, Features and Characteristics Overview
1.19 Tolerance Hierarchy
1.20 Feature Control Frame
1.21 Position and Limit Tolerance General Overview and Contrast
1.22 Common Symbols
1.23 Dimensioning and Tolerancing General Rules

2.1 Limit Tolerancing
2.2 Limit tolerancing, Square Tolerance, Zone and Overview
2.3 Tolerance Application and Method, Basic Dimensions
2.4 Implied 90 Degree Angle, Dimensional Expression
2.5 Dimension and Tolerance Expression – Millimeter Tolerances and Dimensions
2.7 Inch Tolerances and Dimensions
2.9 Oblique, Point and Limited Area Dimensioning
2.11 Dimensions Not to Scale
2.14 Slotted holes, Arcs, Countersink hole
2.15 Countersunk, Counterbored Holes
2.17 Rectangular Coordinate Dimensioning
2.19 Repetitive Features
2.20 Flat Taper
2.21 Conical Taper
2.22 Statistical Tolerancing
2.23 Dimension Origin
2.24 Screw Threads Tolerance Application, Gears and Splines
2.25 Angular Surface Defined by Limit and Angle Dimension
2.26 Radius Tolerance
2.27 Controlled Radius Tolerance
2.28 Knurling, Rods and Tubing Specification, Surface Roughness or Texture
2.29 Features With and Without Size
2.30 Material Condition, MMC, MMB LMC, LMB
2.31 Mating Envelope
2.33 Rule #1, Envelope Principle
2.36 Exceptions to Rule #1, Independency Application
2.37 Rule #2 Material Condition Requirements
2.38 Continuous Feature
2.40 Limitations of the Limits of Size

3.1 Datums
3.2 Immobilization of component and measurement
3.3 Datum identification General
3.4 Datum symbols and identification Datum identification features without size
3.5 Datum identification features with size
3.6 Datum Identification Features with Size Alternative and Special Applications
3.7 Datum associated with feature control frame
3.8 Datum feature, simulated datum, and theoretical datum plane
3.10 Primary External Datum Diameter
3.11 Primary internal Datum Diameter
3.12 Primary External Datum Width
3.13 Primary Internal Datum Width
3.14 Degrees of Freedom
3.15 Planar Datum Feature
3.16 Datum Center Plane Element
3.17 Datum Cylindrical Feature
3.18 Datum Conical Shapes Feature
3.19 Datum Spherical Center Point
3.20 Datum of Linear Extruded Shape
3.21 Datum Linear Tapered Complex Feature
3.22 Primary Datum Features Reference Chart
3.23 Setup and Inspection of Datums
3.25 Sequence of Datum Features
3.27 Parts with Angular Orientation
3.29 Cylindrical Datum Feature
3.30 Orientation of Two Datum Planes Through a Hole
3.32 Datum Reference Frame With Translation Modifier
3.34 Partial Datum Surface(s) as Datum Features
3.35 Partial Contoured Datum Surface
3.38 Multiple Datum Features, Single Datum
3.39 Planar Multiple Datum Features Offset
3.40 Conical Datum Feature Constraining a Rotational Degree of Freedom
3.41 Conical Datum Feature Constraining Rotational Degree of Freedom With secondary Datum Constraint
3.42 Inclined Datum Features

4.1 Datum Targets
4.2 Datum Features and Datum Target Symbols
4.3 Datum Target Point Symbol, Application
4.4 Datum Target Area
4.5 Datum Target Line
4.6 Dimensioning Datum Targets
4.7 Primary Datum Plane Established by Three Datum Target Areas
4.10 Primary Datum Plane Established by Two Datum Target Points and One Datum Target Line.
4.11 Step Datum Feature
4.12 Datum Target Lines and Areas
4.13 Primary Datum Axis Established by Datum Target points on a Single Cylindrical Feature
4.15 Equalizing Datum
4.18 Secondary Datum Axis
4.19 Moveable Datum Targets
4.22 Sheet Metal With Multiple Datum Targets in Restrained Condition

5.1 Form Tolerances
5.2 Flatness
5.3 Flatness Applied on a Unit Basis
5.4 Flatness Applied on Unit Basis With Overall Control
5.5 Flatness Applied to Derived Median Plane at RFS
5.6 Flatness Applied to Derived Median Plane at MMC
5.7 Straightness
5.8 Straightness Per Unit Basis
5.9 Straightness Applied in Two Directions
5.10 Straightness of a Surface (Cylindrical)
5.11 Straightness of a Feature of Size @ RFS
5.12 Straightness of a Feature of Size @ MMC
5.13 Straightness Per Unit Length With Specified Total Straightness
5.14 Cylindricity
5.15 Circularity (Roundness)
5.16 Circularity of Cone
5.17 Circularity of Sphere
5.18 Circularity or Cylindricity Applied with Average Diameter

6.1 Tolerance of Orientation
6.2 Perpendicularity - Surface
6.3 Perpendicularity – Surface Two Datum's
6.4 Perpendicularity – Center plane
6.5 Perpendicularity at MMC Internal Feature – Center Plane
6.6 Perpendicularity – External Feature of Size Axis
6.7 Perpendicularity – Internal Feature of Size Axis
6.8 Perpendicularity –Threaded Hole or Inserts Projected Tolerance Zone
6.9 Parallelism
6.10 Parallelism Control of Two Hole Features
6.11 Parallelism Hole Relative to Plane
6.12 Angularity Overview and Surface to Surface
6.13 Angularity Surface to Surface with Location Control
6.14 Angularity Hole to Planar Datum
6.15 Secondary Datum Application

7.1 Tolerances of Location
7.2 Fundamental Explanation of Positional Tolerancing
7.3 Differences Between Position Tolerancing and Limit Tolerancing
7.4 Modifiers
7.5 Maximum Material Condition and Boundary
7.6 Least Material Condition and Boundary
7.7 External Feature of Size Position Tolerance Boundaries with Maximum Material Condition MMC Specification and Datum's at RMB
7.8 Internal Feature of Size Position Tolerance Boundaries with Maximum Material Condition MMC Specification and Datum's at RMB
7.9 External Feature of Size Position Tolerance Boundaries with Least Material Condition LMC Specification and Datum's at RMB
7.10 Internal Feature of Size Position Tolerance with Least Material Condition LMC Specification and Datum's at RMB
7.11 Zero Positional Tolerance at MMC, Datum's at RMB
7.12 Position Tolerance at RFS and Datum's at RFB
7.13 Positional Tolerance at MMC Surface and Axis Interpretation of a Hole Feature
7.14 Positional Tolerance Axis and Surface Interpretation – Surface Datum's
7.15 Positional Tolerance Axis Interpretation - Surface Datum's
7.16 Positional Tolerance Surface Interpretation - Surface Datum's
7.17 Positional Tolerance Axis and Surface Interpretation - Thru Hole Datum's
7.18 Positional Tolerance Axis Interpretation – Thru Hole Datum's
7.19 Positional Tolerance Surface Interpretation – Thru Hole Datum's
7.20 Rectangular Coordinate Method
7.21 Positional Tolerance at MMC Relative to Hole and Slot Datum Feature
7.22 Bi-Directional Positional Tolerancing, Polar Coordinate Method
7.23 Different Positional Tolerance at Each Surface
7.24 Circular Pattern of Holes
7.25 Positional Tolerance at MMC Relative to Datum Feature Center Planes
7.26 Positional Tolerance at RFS of Slots Relative to Surface Datum Features
7.27 Coaxial (Concentric) Control of Cylinders
7.28 Coaxial (Concentric) Control of Multiple Hole-Counterbore Holes
7.29 Coaxial Control of Cylinders
7.30 Hole Pattern Located Perpendicular to Cylindrical Datum
7.31 Holes Not Normal to DRF
7.32 Hole Pattern Located at Angle to Datum Reference Frame
7.33 Positional Tolerance at MMC of Spherical Feature
7.34 Positional Tolerance of Coaxial Holes of Same Size
7.35 Calculating Maximum Material Boundary (MMB )
7.36 Least Material Condition Application – Cylinder Wall Thickness
7.37 Positional Tolerance for Coaxiality With Datum Feature referenced at MMB
7.38 Positional Tolerance for Coaxially With Feature Referenced at Zero MMC Relative to Datum Feature at MMB
7.39 Variable Tolerance Boundary Minimum at Nominal Size
7.40 Positional Tolerance - Thru Hole Datum's at MMC
7.41 Positional Tolerance - Thru Hole Datum Verification
7.42 Composite Positional Tolerancing
7.46 Composite Positional Tolerancing With Pattern Orientation Control
7.49 Concentricity
7.51 Concentricity Application
7.52 Concentricity of Sphere
7.53 Symmetry

8.1 Profile Tolerances
8.2 Profile Surface Definition
8.3 Profile of surface, Bilateral Tolerance
8.4 Profile of Surface, Bilateral Tolerance Between Symbol Alternative Practice
8.5 Profile of Surface, Bilateral Tolerance Rectangular Coordinate Dimensioning Without Dimension Lines
8.6 Profile of Surface, Unilateral (INSIDE) Tolerance
8.8 Profile of Surface, Unilateral (OUTSIDE) Tolerance
8.12 Profile of Surface, Bilateral Unequal Tolerance
8.14 Profile of Surface, All Around
8.15 Profile of Surface, All Over
8.16 Profile of Surface, Independent Form Control
8.17 Profile of Surface, Boundary Principle
8.18 Profile Tolerance for Coplanar Surfaces
8.20 Profile of Line
8.21 Profile of Line Tapered Shape
8.22 Profile of Line Unilateral Inside
8.24 Profile of Line and Size Control
8.25 Profile of Line and Size Control
8.26 Composite Profile Tolerances
8.27 Composite Profile Tolerance With Rotation Control of PRC
8.29 Non-Uniform Zone
8.30 Non-Uniform Zone Application
8.31 Profile of Surface With Datum at MMC

9.1 Runout Tolerances
9.2 Circular Runout
9.5 Total Runout
9.8 Run-Out With Plane as Datum
9.9 Run-Out Relative to Datum Surface and a Diameter
9.10 Run-Out With Two Datum Diameters
9.11 Multiple Cylinders Related to Each Other Runout Application
9.12 Runout Relating Separate Features to Each Other with Common Datum

10.1 Coaxial Tolerance Comparison
11.1 Tolerance Analysis
11.3 Tolerance Conversion Unilateral, Bilateral
11.4 Series Stack
11.5 Floating Fastener Condition
11.6 Fixed Fastener Condition
11.7 Tolerance Compensation for Projected Tolerance Zone – Fixed Fastener condition
11.9 Two Mating Coaxial/Coplanar Features at MMC
11.10 Three Mating Coaxial/Coplanar Features at MMC

11.11 Six Sigma Concepts
11.12 Increasing the Cp Level to Reach Six Sigma
11.13 Graphical Representations of Distributions
11.16 Linear Six Sigma Calculations
11.17 Linear Three Sigma Calculations
11.18 Position Tolerance Calculation and Hole Pattern Analysis
11.20 Coordinate to Position Tolerance Conversion Chart
11.25 Generic Hole Verification Chart

12.1 Critical Feature Drawing (Reduced Dimension Drawing)
12.2 Implementation Considerations Applicable Documents, Overview
12.3 Design Drawing Requirements Digital Model and Database
12.4 Quality and Inspection Requirements Manufacturing
12.5 Change Notice Procedure

13.1 3D Drafting and Model Digital Product Definition Data Practices
13.2 Definitions and Terminology
13.3 Fundamental Dimensioning and Tolerancing Requirements
13.6 Left-Hand and Right-Hand Model Coordinate System Requirements
13.7 3D Model with All Annotation Displayed
13.10 3D Model With Datum Target Annotation
13.14 Attachment Techniques, Fillets, Rounds, and Chamfers
13.15 Attachment Techniques, Countersinks and Oblique Surfaces
13.16 Attachment Techniques, Reliefs and Step Surfaces
13.17 Attachment Techniques, Depth, Spotface, Remaining Thickness
13.18 Attachment Techniques, Notches, Flats, and Pin Heights
13.19 Datum Applications
13.20 Datum System and Coordinate Relationship
13.22 Datum Feature Symbol Attachments
13.23 Partial Datum Features
13.25 Datum Axis From Cylinder
13.27 Two Coaxial Features Establish a Datum Axis
13.28 Coplanar Surfaces Establish a Datum Plane
13.28 Separated Surfaces Establish a Datum Plane
13.29 Flatness Coincident or Perpendicular Annotation Plane
13.30 Flatness Tolerance
13.31 Straightness Directed by Line Element
13.34 Circularity Annotation Methods
13.35 Cylindricity Annotation Methods
13.36 Orientation Tolerances Planar Surfaces
13.40 Profile of Planar, Conical, or Revolved Surface
13.43 Position Tolerance Annotation Methods
13.45 Position Tolerance of Elongated Holes or Slots
13.46 Bi-Directional Position Tolerances Polar or Rectangular
13.47 Position Combined with Profile
13.48 Concentricity and Symmetry Tolerances Annotation Methods
13.49 Runout Tolerances Attachment and Associativity
13.52 Design Model Section View / Cutting Plane

14.1 GD&T Symbol Comparison
14.2 Comparison of ASME and ISO Symbols (Geometric Characteristics)

15.1 Appendix – Geometric Characteristic Symbol Proportions and Size
15.4 Design Decision Chart
15.5 Datum Selection Decision Chart
15.6 Form Tolerances Decision Chart
15.7 Orientation Tolerances Decision Chart
15.8 Location Tolerances Decision Chart
15.9 Profile Tolerances Decision Chart
15.10 Runout Tolerances Decision Chart
15.11 ANSI Standard Size (Inch) Drills
15.12 ISO Metric (mm) Size Standard Drill Sizes
15.13 ANSI External Screw Threads Sizes 0 - 3/8
15.13 ANSI External Screw Threads Sizes 3/8 – Larger "
15.14 ACME Thread Forms – General Purpose External
15.16 ACME Thread Forms – General Purpose Internal
15.17 ACME Thread Forms – Internal Centralizing
15.18 ACME Thread Forms – External Centralizing
15.19 Standard External Pipe Threads
15.20 Standard Internal Pipe Threads


The following documents have been used as reference material (cited and not cited).

Engineers Edge 2000 - 2019, Solutions by Design –
Design for Manufacturing 2006 - 2019, Kelly Bramble
Geometric Boundaries II, Based on ASME 14.5-2009
Geometric Boundaries Based on ASME Y14.5M-1994
Geometrical Boundaries Based on ISO 1101(E) 2004, Kelly Bramble
ANSI/ASME B94.6-1984 (R2003), Knurling
ANSI B4.2-1978 (R2004), Preferred Metric Limits and Fits
ASME Y14.5-2009, Dimensioning and Tolerancing.
ASME Y14.5.M-1994, Dimensioning and Tolerancing
ANSI Y14.5M-1982, Dimensioning and Tolerancing
ANSI Y14.5M-1973, Dimensioning and Tolerancing
ANSI Y14.5M-1966, Dimensioning and Tolerancing
ISO/R1101 (E)-2004, & Associated Documents
ANSI B4.2-1978, Preferred Metric Limits and Fits
ANSI B5.10-1981, Machine tapers – Self Holding and Steep Taper Series
ANSI/ASME B46.1-1985, Surface Texture (Surface Roughness, Waviness, and Lay)
ANSI B89.3.1-1972, Measurement of Out-of-Roundness
ANSI/ASME B89.6.2-1973 (R2003), Temperature and Humidity Environment for Dimensional Measurement
ANSI B92.1-1970, Involute Splines and Inspection, Inch Version
ANSI B92.2M-1980, Metric Module, Involute Splines
ANSI/ASME B94.6-1984, Knurling
ANSI B94.11M-1979, Twist Drills
ANSI Y14.1-1980, Drawing Sheet Size and Format
ASME Y14.1M-2005, Metric Drawing Sheet Size and Format
ASME Y14.2M-1992, Line Conventions and Lettering
ASME Y14.2-2008, Line Conventions and Lettering
ASME Y14.5.1M-1994, Mathematical Definition of Dimensioning and Tolerancing Principles.
ANSI Y14.6aM-1981 (R1998), Screw Thread - Representation (Metric Supplement)
ANSI Y14.6.1-1978, Screw Thread Representation
ANSI Y14.6.2-1981, Screw Thread Representation (Metric Supplement)
ANSI Y14.7.1-1971, Gear Drawing Standards – Part 1: For Spur, Helical, Double Helical, and Rack
ANSI Y14.7.2-1978, Gear and Spline Drawing Standard – Part 2: Bevel and Hypoid Gears
ASME Y14.8M-1989, Castings and Forgings
ANSI Y14.36-1978, Surface Texture Symbols
ANSI/IEEE 268-1992, Metric Practice
ANSI/ASME B1.2-1983, Gauges and Gauging for Unified Inch Screw Threads
ANSI B4.4M-1981 (R1987), Inspection of Workpieces
ASME B5.10-1994, Machine Tapers — Self Holding and Steep Taper Series
ASME Y1.1-1989, Abbreviations
ASME Y14.3M-1994, Multiview and Sectional View Drawings
ASME Y14.41-2003 (R2008), Digital Product Definition Data Practices
ASME Y14.43-2003 (R2008), Dimensioning and Tolerancing Principles for Gages and Fixtures
IEEE/ASTM SI 10-2002 ERRATA 2005, Standard for Use of the International System of Units (SI) — The Modern Metric System