Course Content. Day 1, Morning Introduction to GD&T What is GD&T, GD&T Definition & Application of GD&T Definition of GD&T What is Dimensioning & Tolerances. Exercise : Simple definition on Geometry, Dimensioning and Tolerance. Dimension Standards for GD&T. ASME , ISO & Din Standards Direct Tolerancing Methodology Application examples on sizes and dimension with lecture with some simple illustration Exercises Sample Lead frame example. Application using lead frame sample Course Content. Day 1, Noon Common Symbols in GD&T. List of symbols and their interpretation Assessment Geometric Characteristic Symbols Symbols application Datum reference application to various symbols Assessment Exercise Composite Tolerancing Example and exercise Rules for Drawing and Designs Envelope Principle. Rules for Gear and Splines. Regardless of feature size.(RFS) settings Maximum Material Condition (MMC) Least Material Condition (LMC). Virtual Condition and Resultant Condition. Case studies: Interpretation of drawing and designs involved hardware components Exercise Study of tolerancing condition Maximum Material Condition (MMC), Least Material Condition (LMC) and Regardless of Feature Size (RFS) application and interpretation

1. Geometric Dimensioning & Tolerancing
(GD&T)
23-24th Aug 2017
For: Virtue Technology Sdn Bhd
Address: PLOT 202, Lorong Per. Bukit
Minyak 11, Kaw Per. Bkt Minyak,
14100 Bukit Tengah, Penang
Presented by: Timothy Wooi
For: JMC Group of Companies
Geometric Dimensioning & Tolerancing (GD&T)

2. Course Content. Day 1, Morning
Introduction to GD&T
• What is GD&T, GD&T Definition &
Application of GD&T
Definition of GD&T
• What is Dimensioning & Tolerances.
• Exercise : Simple definition on
Geometry, Dimensioning and
Tolerance.
• Dimension
Standards for GD&T.
• ASME , ISO & Din Standards
Direct Tolerancing
Methodology
Application examples on sizes
and dimension with lecture with
some simple illustration
Exercises
• Sample Lead frame example.
• Application using lead frame
sample
Geometric Dimensioning & Tolerancing (GD&T)

3. Course Content. Day 1, Noon
Common Symbols in GD&T.
• List of symbols and their interpretation
Assessment
Geometric Characteristic Symbols
• Symbols application
• Datum reference application to various
symbols
• Assessment Exercise
• Composite Tolerancing
• Example and exercise
Geometric Dimensioning & Tolerancing (GD&T)
Rules for Drawing and Designs
Envelope Principle.
Rules for Gear and Splines.
Regardless of feature size.(RFS) settings
Maximum Material Condition (MMC)
Least Material Condition (LMC).
Virtual Condition and Resultant Condition.
Case studies:
Interpretation of drawing and designs
involved hardware components
Exercise
Study of tolerancing condition
Maximum Material Condition (MMC),
Least Material Condition (LMC) and
Regardless of Feature Size (RFS)
application and interpretation

4. Day-2, Morning
Simultaneous Requirements for Combined parts
Profile Controls
 Profile tolerancing
- Computation of holes in relation to leading hole in
various materials condition.
 Composite Position Tolerance
- Application of the condition to achieve better
machine settings.
Exercise
 Computation and interpretation
Geometric Dimensioning & Tolerancing (GD&T)
Two Single Segment Feature Control Frame
- Interpretation and understanding
- Exercises and examples - Assessment test:
-Using GD&T on various component, interpret fabrication of parts successfully
considering business factors.

5. Day-2, Noon
Geometric Dimensioning & Tolerancing (GD&T)
Inspection for proper Tolerances &
Dimensioning
- Appropriate and correct approach of during
inspection.
- Correct position and method of measurement of
parts based on the technical drawings.
- Datum & relevant Selection
- Definition of datum reference frame –
Definition of datum reference points
-Decision Diagrams
Study of Sample Drawings
-Exercise and Workshop: Interpretation of sample
mechanical drawings.
-Convert from +/- to true position tolerancing
Conclusion and Q & A session
End of day 2

6. GD&T Course Objective
(Based on ASME Y14.5M-1994)
Geometric Dimensioning & Tolerancing (GD&T)
To allow Participants to master
techniques of GD&T in the
ASME standard to;
integrate smoothly into
engineering design applications
and modern inspection systems
at work.
Provide Participants with Fundamental concepts of GD&T
to express, understand and interpret drawing requirements
using GD&T to ANSI / ASME Y14.5M Standards.

7. GD&T: An
International
Language
GD&T: An Exact
Language
GD&T Provides
Uniformity
What is GD&T?
Introduction to GD&T

8. GD&T stands for Geometric Dimensioning and
Tolerancing, as defined by ASME Y14.5
Introduction to GD&T
GD&T: An International
Language
GD&T is an international
system of symbolic language
used on drawings to
accurately describe a part.
Definition

9. GD&T: An Exact Language
Geometric tolerancing is an exact language that
enables designers to “say what they mean” on a
drawing, thus improving product designs.
Production uses the
language to interpret
the design intent, and
inspection looks to the
language to determine
set up.
Introduction to GD&T

10. GD&T is a method for stating and interpreting
mechanical engineering design requirements.
GD&T is a very useful &
efficient tool to make
engineering drawings a
better means of
communication from
design through
manufacturing and
inspection.
Introduction to GD&T

11. GD&T Provides Uniformity
By providing uniformity in drawing specifications
and interpretation, GD&T reduces;
controversy,
guesswork, and
assumptions
throughout the
manufacturing and
inspection process.
Introduction to GD&T

12. Language of GD&T
The language consists of a well-defined set of
symbols, rules, definitions, and conventions that
can be used to describe the;
size,
 form,
orientation, and
 location tolerances
of part features.
Introduction to GD&T

13. Application & Advantages of GD&T
The advantages of applying GD&T in design
specifications are:
Uniformity in design
practice
Clear interpretation of
tolerance classification.
Ensure interchangeability
Maximum tolerance
allocation.
Introduction to GD&T

14. In-depth knowledge of GD&T application allows
optimum form, fit & function between the
various complex pieces of parts assembly.
Starting with basic principles
in coordinate dimensioning
& tolerancing and
progressing on these
principles to understand &
apply GD&T requirements to
ad concepts to real work
applications.
Introduction to GD&T

15. Before an object can be built, complete information
about both the size and shape of the object must be
available.
Definition of GD&T
The exact shape of an
object is communicated
through orthographic
drawings, which are
developed following
standard drawing
practices.

16. Definition of GD&T
The process of adding size information to a drawing is
known as dimensioning the drawing.

17. Definition of GD&T
Geometrics is the science of specifying and tolerancing
the shapes and locations of features on objects.
Once the shape of a
part is defined with an
orthographic drawings,
the size information is
added also in the form
of dimensions.

18. Definition of GD&T
Dimensioning a drawing also identifies the tolerance
(or accuracy) required for each dimension.

19. GdnT Rules Based System
Dimension
Geometric Dimensioning & Tolerancing (GD&T)

20. Dimensioning standards play a critical role in the
creation and interpretation of engineering drawings.
They provide a uniform set of symbols, definitions, rules,
and conventions for dimensioning.
Standards for GD & T. – ASME, - ISO, - Din
Without
standards,
drawings
would not be
able to
consistently
communicate
the design
intent globally.
ANSI - American National Standards Institute
- This institute creates the engineering standards for
North America.
ISO - International Organization for Standardization
- This is a world wide organization that creates engineering standards
with approximately 100 participating countries.
DIN - Deutsches Institut für Normung
- The German Standards Institute created many standards used
world wide such as the standards for camera film.
JIS - Japanese Industrial Standard
- Created after WWII for Japanese standards.
CEN - European Standards Organization

21. Standards for GD & T. – ASME, - ISO, - Din
These two standards have
emerged as the primary
dimensioning standards.
There are also several other
standards that are in use in
lesser degree eg. Deutsche
Industrie Norm (DIN)
standard.
There is increasing pressure to migrate toward a common
international standard as the world evolves toward a
global marketplace.
Most dimensioning standards used in industry are based
on either the American Society of Mechanical Engineers
(ASME) or International Organization for Standardization
(ISO) standards.

22. ASME is an engineering society focused on mechanical
engineering in North America, is thus a standards organization,
a research and development organization, a provider of training and
education, and a nonprofit organization.
- A document that communicates a precise description of a part.
- This description consists of pictures, words, numbers, and symbols.
Standards for GD&T. (ASME),
American Society of Mechanical Engineers.

23. This standard was
created to unify design
and interpretation,
minimizing errors in the
production of parts and
assemblies.
In 1982, the first GD&T (Geometric Dimensioning and
Tolerancing) standards were introduced to the ASME.
Standards for GD&T. (ASME),
American Society of Mechanical Engineers.
The standard was revised in 1994 and again in 2009.

24. Standards for GD & T. – ASME, - ISO, - Din
ASME Standards
ASME Y14.5 – Dimensioning and
Tolerancing
ASME Y14.5M-1994 Dimensioning and
Tolerancing
ASME Y14.5.1M-1994 Mathematical
Definition of Dimensioning and
Tolerancing Principles
Many multi-national corporations use ASME Y14.5
(ASME Y14.5M-1994 or ASME Y14.5-2009) as their
GD&T standard worldwide for their international
operations.
The ASME Y14.5
standard is
considered the
authoritative
guideline for the
design language of
GD&T.
ASME Y14.5-2009 is a replacement of ASME
Y14.5M-1994.

25. Now, a consensus committee of experts has revised
ASME Y14.5 for 21st-century applications.
Important changes address:
 concept of feature of size;
 datum references and degrees of
freedom;
 composite position tolerances;
 surface boundaries and axis
methods of interpretation;
 profile tolerances; and
 symbology and modifiers tools.
Additionally, the subject matter has been restructured for
better readability, with profile, orientation, and form now in
separate sections, and material within sections reorganized.)
Standards for GD&T. (ASME),
American Society of Mechanical Engineers.
ASME Revisions
ASME Y14.5
Dimensioning and
Tolerancing
ASME Y14.5M-1994
Dimensioning and
Tolerancing

26. ISO 1101:2004
Geometrical Tolerancing.
Standards for GD & T. – ASME, - ISO, - Din
The International Organization for Standardization (ISO)
also has a version of GD&T, which they call ISO 1101
Geometrical Dimensioning and Tolerancing (GD&T).
At present the ISO
standards do not recognize
the interpretation of
concentricity and symmetry
as defined in the ASME
Y14.5 standard.
The concentricity and symmetry characteristics in ISO
have the same interpretations as the position
characteristic in the ASME Y14.5M 1994 standard.

27. Differences between the ASME and ISO for GD&T
Nomenclature differences
Other Differences:
1. In ASME the rule #1 controls Size and Form simultaneously.
In ISO, Form is independent of Size and is additive to size.
An encircled E symbol in ISO invokes the envelope principle in ISO.
ASME ISO
Basic Dimension Theoretically Exact Dimension
Feature Control Frame Tolerance Frame
Reference Dimension Auxiliary Dimension
True Position Theoretically Exact Position

28. Other Differences:
2. General Tolerances are not covered under ASME. General
tolerances can beapplied in ISO drawings by putting a note ISO-2768.
When ISO-2768 is referred on the drawing, general tolerances are
invoked on linear and angular dimensions.
3. ASME does not specially define non-rigid parts as separate entities.
A F-modifier is used to show that the geometry should be checked
under Free State. ISO shows non-rigid parts by putting a note stating
ISO-10579-NR in the title block.
4. Under ASME, tolerance zones are always Normal to the geometry.
Under ISO,you can define tolerance zones that are at another angle to
the geometry.
5. ASME defaults to third-angle projection. ISO defaults to first-angle
projection
Differences between the ASME and ISO for GD&T

29. Other Differences:
6. Under ASME datum feature leader cannot point towards axes and
Center planes. Under ISO the datum feature leader can point to an
axis or a Center plane.
7. Under ASME, datum precedence has to be strictly maintained.
Under ISO, ambiguous order of datums is allowed, so long as the
order is not important.
8. Under ASME, composite position tolerances are interpreted as
PLTZF and FRTZF. Under ISO, the two segments of a composite
position tolerance frame are interpreted as separate tolerances.
9. Under ASME, Concentricity and Symmetry are always applied RFS.
Under ISO they can be applied at MMC, LMC or RFS.10. ASME
is a single standard. ISO has collection of standards addressing various
Geometric tolerances.
Differences between the ASME and ISO for GD&T

30. Application examples on sizes and dimensions.
Dimensioning and tolerancing philosophy -
Fundamental Rules.
Direct Tolerancing Methodology
There are some
Fundamental Rules
that need to be
applied.
These can be found on
the GD&T Rule Based
System.
Fundamental Rules
Exercises

31. Course Content. Day 1, Noon
Common Symbols in GD&T.
• List of symbols and their interpretation
Assessment
Geometric Characteristic Symbols
• Symbols application
• Datum reference application to various
symbols
• Assessment Exercise
• Composite Tolerancing
• Example and exercise
Geometric Dimensioning & Tolerancing (GD&T)
Rules for Drawing and Designs
Envelope Principle.
Rules for Gear and Splines.
Regardless of feature size.(RFS) settings
Maximum Material Condition (MMC)
Least Material Condition (LMC).
Virtual Condition and Resultant Condition.
Case studies:
Interpretation of drawing and designs
involved hardware components
Exercise
Study of tolerancing condition
Maximum Material Condition (MMC),
Least Material Condition (LMC) and
Regardless of Feature Size (RFS)
application and interpretation

32. Common Symbols in GD&T.
List of symbols and their interpretation Assessment
Common Symbols in GD&T
Exercise
Study of tolerancing condition
Maximum Material Condition (MMC),
Least Material Condition (LMC) and
Regardless of Feature Size (RFS)
application and interpretation
GD&T Symbols

33. Geometric Characteristic Symbols
Symbols application
• Datum reference application to various symbols
• Assessment Exercise
• Composite Tolerancing
• Example and exercise
Common Symbols in GD&T
Exercise

34. Rules for Drawing and Designs
Envelope Principle.
• Rules for Gear and Splines.
• Regardless of feature size.(RFS)
settings
• Maximum Material Condition
(MMC)
• Least Material Condition (LMC).
• Virtual Condition and Resultant
Condition.
Geometric Dimensioning & Tolerancing (GD&T)
Rules

35. Case studies:
Interpretation of drawing and designs involved hardware
components
Geometric Dimensioning & Tolerancing (GD&T)
Workshop Examples

36. Common Symbols in GD&T
Exercise
Study of tolerancing condition
Maximum Material Condition (MMC),
Least Material Condition (LMC) and Regardless of Feature
Size (RFS) application and interpretation
Exercise

37. Day-Two, Morning
Simultaneous Requirements for Combined parts
Profile Controls
 Profile tolerancing
- Computation of holes in relation to leading hole in
various materials condition.
 Composite Position Tolerance
- Application of the condition to achieve better
machine settings.
Exercise
 Computation and interpretation
Geometric Dimensioning & Tolerancing (GD&T)
Two Single Segment Feature Control Frame
- Interpretation and understanding
- Exercises and examples - Assessment test:
-Using GD&T on various component, interpret fabrication of parts successfully
considerating business factors.

38. Day-Two Noon
Geometric Dimensioning & Tolerancing (GD&T)
Inspection for proper Tolerances & Dimensioning
- Appropriate and correct approach of during
inspection.
-Correct position and method of measurement of
parts based on the technical drawings.
-Datum & relevant Selection
-- Definition of datum reference frame –
Definition of datum reference points
-Decision Diagrams
Study of Sample Drawings
-Exercise and Workshop: Interpretation of sample
mechanical drawings.
-Convert from +/- to true position tolerancing
Conclusion and Q & A session
End of day 2

39. Thank You!
End of Day 1
Geometric Dimensioning & Tolerancing (GD&T)