1. Complimentary slides to Chris Monnier at Boston Scientific
International Institute of GD&T
Precision GD&T:
Complimentary slides to Chris Monnier at Boston Scientific
Dr. Greg Hetland, President
International Institute of GD&T

2. Plus / Minus Tolerancing
This method of tolerancing allows the axis of the hole to move plus something and minus something in the X and Y direction.
This creates a square tolerance zone in which the holes must lie?
4X 
25  0.1
0.1
0.1
50  0.1

3. Linear Transformation to GD&T
Geometric Dimensioning & Tolerancing (GD&T) creates cylindrical tolerance zones by removing the tolerance from the dimensions and applying it to the features. In this example, the geometric control is position. Dimensions are basic boxed , theoretically exact, with no tolerance.
4X 

Position Symbol
Diameter Symbol
Total Tolerance 25 50

4. Feature Control Frame 
Geometric Characteristic
Diameter Symbol
Feature Tolerance
Feature Modifier
Projected Tolerance Zone Symbol
Height of Projected Tolerance Zone
Primary Datum
Secondary Datum
Datum Modifier
Tertiary Datum


5. Profile Comparison to Linear…

6. Tolerancing Consideration #1
20.02
20.06
20.1
20.14
20.04
20.08
20.12
20.16
20.18
20.22
20.26
20.2
20.24 20
19.74
19.78
19.82
19.86
19.76
19.8
19.84
19.88
19.9
19.94
19.98
19.92
19.96
0.1
0.06
0.02
0.12
0.08
0.04
0.14
0.24
0.2
0.16
0.26
0.22
0.18
Virtual Condition
MMC
LMC
20±0.2







20±0.2






 
Only in Diagonals

7. Tolerancing Consideration #5


















20.02
20.06
20.1
20.14
20.04
20.08
20.12
20.16
20.18
20.22
20.26
20.2
20.24 20
19.74
19.78
19.82
19.86
19.76
19.8
19.84
19.88
19.9
19.94
19.98
19.92
19.96
0.1
0.06
0.02
0.12
0.08
0.04
0.14
0.24
0.2
0.16
0.26
0.22
0.18
Virtual Condition 
MMC
LMC








20±0.2
20±0.2

8. GD&T Boundary Comparisons               Orientation Form
Angularity 
Perpendicularity
Form  
Straightness
Parallelism
Location  
Flatness
Position  
Circularity
Concentricity  
Cylindricity
Symmetry
Profile
Runout  
Profile of a
Surface
Circular Runout 
Profile of a
Line 
Total Runout

9. Global Simplification of GD&T
Flatness 
3D Surface
Control
Angularity  
Perpendicularity  
Parallelism 
Profile of a
Surface
Cylindricity 
Total Runout
Concentricity 
Symmetry  
2D Surface
Control
Straightness  
Circularity 
Profile of a
Line
Circular Runout 
Axis Control
Straightness 
Angularity  
Perpendicularity 
Parallelism
Position
Concentricity 
Symmetry 

10. GD&T Training Deployment Guide Beginning Operators & Technicians
Customers
Individuals who need to understand terminology & graphical representation of an engineering drawing.
Sales & Purchasing
Beginning Operators & Technicians
Course I
Machinists
Tool Makers
Senior Inspectors
Senior Technicians
Engineers:
Associate Engineers
Engineers
Senior Engineers
Principal Engineers
Fellow Engineers
Course III
Drafters
Inspectors
Machine Operators
Technical Managers
Technicians:
Associate Technicians
Technicians
Course II
Supplier Technicians
Supplier Engineers
Receiving Inspectors
Rec. Inspection Techs.
Measurement Engineers
Suppliers
Purchasing
Process Technicians
Process Engineers
Measurement Technicians
Measurement Engineers Quality-Technicians
Quality-Engineers
Designers
Exec.
Level
Manufacturing
Quality/Measurement
Design
Tool Room
Administration
Sales/Applications
Sales
Executives
Course 1: Basic Blueprint Reading
Course 2: GD&T - Introduction & Fundamental Principles
Course 3: GD&T – Advanced Applications & Analysis

11. IIGDT Public & In-House Courses
Basic Blueprint Reading (1-day)
To understand basic components, sections, views, terminology and graphical representation of an engineering drawing.
GD&T- Introduction & Fundamental Principles (2-day)
To provide fundamental lessons in proper interpretation of engineering drawings used in the design, manufacture and inspection of parts which have geometric controls applied per ANSI Y14.5M and ASME Y14.5M-1994.
GD&T- Advanced Applications & Analysis (2-day)
To provide advanced information in "applications and analysis“
(per ASME Y14.5M-1994 and ASME Y14.5.1M-1994) involving optimization strategies for given design applications, manufacturing methodologies and measurement implications.
Public seminars scheduled quarterly at the University of Minnesota
50% Discount to Students and Professors
See for details

12. GD&T GUIDE Charts ($12 each) available on-line at or
calling IIGDT at
sending and to:

13. GD&T Fonts ($49 each) available by calling IIGDT at 952-936-9499 or
sending and to: