This document provides information on geometric dimensioning and tolerancing (GD&T). It discusses the three categories of dimensioning, including general, geometric, and surface texture. GD&T considers the function of a part and how parts interact. GD&T uses standard symbols to indicate tolerances based on a feature's geometry. GD&T aims to more precisely define features without increasing tolerances. Key aspects of GD&T covered include datums, maximum and least material conditions, tolerance zones, and feature control frames. Specific GD&T controls like perpendicularity, angularity, parallelism, and their symbols are explained. The importance of GD&T for functions like interchangeability is emphasized.
GD&T is an international way of describing a part accurately. It is used widely in all manufacturing sectors for part dimensioning. This ppt contains basic overview of GD&T. The detailed version will be uploaded soon.
A basic 2 day training on understanding of GDnT,Geometrical Dimensioning & Tolerancing to Technical & Egineering Group as a common language in understanding Drawings.
Trainer & Speaker
Timothy Wooi,
20C,Taman Bahagia,06000,Jitra, Kedah. Malaysia
email: timothywooi2@gmail.com
GD&T is an international way of describing a part accurately. It is used widely in all manufacturing sectors for part dimensioning. This ppt contains basic overview of GD&T. The detailed version will be uploaded soon.
A basic 2 day training on understanding of GDnT,Geometrical Dimensioning & Tolerancing to Technical & Egineering Group as a common language in understanding Drawings.
Trainer & Speaker
Timothy Wooi,
20C,Taman Bahagia,06000,Jitra, Kedah. Malaysia
email: timothywooi2@gmail.com
Geometric dimensioning and tolerancing is the new way of describing the dimensions and tolerances. It developed by engineers and used by engineers in engineering drawings or drafting. It plays a very important role in engineering design.
This presentation contains all the basic information about GD&T.
GD&T for Omega Fabrication, Melaka.4-5th March 2017Timothy Wooi
GD&T Course Objective
Provide Participants with Fundamental concepts of GD&T to express, understand and interpret drawing requirements using GD&T to ASME Y14.5 Standards.
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.
This PPT discuss the 14 geometric symbols used in GD&T classified under five controls. Only important points are mentioned. Kindly mention, if any other important points are missed out. The sources of the content (including pics) are from various sites which details GD&T. The PPT with modifiers and additional symbols (in detail) will be updated soon.
This ppt describes Profile & Runout CONTROLS in GD&T. It also showcase the differences & similarities between the two controls. Kindly suggest your comments as required. Thank you + Regards.
Geometric dimensioning and tolerancing is the new way of describing the dimensions and tolerances. It developed by engineers and used by engineers in engineering drawings or drafting. It plays a very important role in engineering design.
This presentation contains all the basic information about GD&T.
GD&T for Omega Fabrication, Melaka.4-5th March 2017Timothy Wooi
GD&T Course Objective
Provide Participants with Fundamental concepts of GD&T to express, understand and interpret drawing requirements using GD&T to ASME Y14.5 Standards.
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.
This PPT discuss the 14 geometric symbols used in GD&T classified under five controls. Only important points are mentioned. Kindly mention, if any other important points are missed out. The sources of the content (including pics) are from various sites which details GD&T. The PPT with modifiers and additional symbols (in detail) will be updated soon.
This ppt describes Profile & Runout CONTROLS in GD&T. It also showcase the differences & similarities between the two controls. Kindly suggest your comments as required. Thank you + Regards.
Medición de los parámetros "twist" de rugosidad, nuevos requerimientos de medición en la industria automotriz. Jenoptik a incorporado la metodología y evaluación de este parámetro en nuestros software.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
1. PART PRODUCTION COMMUNICATION MODEL
MANAGEMENT
DESIGN
TOOLING
PRODUCTION
INSPECTION
ASSEMBLY
ROUTING
PLANNING
PRICING
SERVICE
PURCHASING
SALES
CUSTOMERSVENDORS
Geometric Dimensioning
and Tolerancing (GD&T)
Geometric Dimensioning
and Tolerancing (GD&T)
2. Dimensioning can be divided into
three categories:
•general dimensioning,
•geometric dimensioning, and
•surface texture.
The following provides
information necessary to begin to
understand geometric
dimensioning and tolerancing
(GD&T)
Three Categories of
Dimensioning
Three Categories of
Dimensioning
6. Geometric
Dimensioning &
Tolerancing (GD&T)
Geometric
Dimensioning &
Tolerancing (GD&T)
GD&T is a means of
dimensioning & tolerancing
a drawing which considers
the function of the part and
how this part functions
with related parts.
– This allows a drawing to
contain a more defined
feature more accurately,
without increasing tolerances.
7. GD&T cont’dGD&T cont’d
GD&T has increased in practice in
last 15 years because of ISO
9000.
– ISO 9000 requires not only that something
be required, but how it is to be controlled.
For example, how round does a round
feature have to be?
GD&T is a system that uses
standard symbols to indicate
tolerances that are based on the
feature’s geometry.
– Sometimes called feature based
dimensioning & tolerancing or true
position dimensioning & tolerancing
GD&T practices are specified in
ANSI Y14.5M-1994.
8. For ExampleFor Example
Given Table Height
However, all surfaces have a degree of
waviness, or smoothness. For
example, the surface of a 2 x 4 is
much wavier (rough) than the surface
of a piece of glass.
– As the table height is dimensioned, the
following table would pass inspection.
If top must be flatter, you could tighten
the tolerance to ± 1/32.
– However, now the height is restricted to
26.97 to 27.03 meaning good tables would
be rejected.
Assume all 4 legs will be
cut to length at the same
time.
or
9. Example cont’d.Example cont’d.
You can have both, by using
GD&T.
– The table height may any height
between 26 and 28 inches.
– The table top must be flat within
1/16. (±1/32)
27
.06
26
.06
28
.06
10. WHY IS GD&T IMPORTANTWHY IS GD&T IMPORTANT
Saves money
– For example, if large number
of parts are being made –
GD&T can reduce or eliminate
inspection of some features.
– Provides “bonus” tolerance
Ensures design, dimension, and
tolerance requirements as they
relate to the actual function
Ensures interchangeability of
mating parts at the assembly
Provides uniformity
It is a universal understanding of
the symbols instead of words
11. WHEN TO USE GD&TWHEN TO USE GD&T
When part features are critical to
a function or interchangeability
When functional gaging is
desirable
When datum references are
desirable to ensure consistency
between design
When standard interpretation or
tolerance is not already implied
When it allows a better choice of
machining processes to be made
for production of a part
12. TERMINOLOGY REVIEWTERMINOLOGY REVIEW
Maximum Material Condition
(MMC): The condition where a size
feature contains the maximum amount
of material within the stated limits of
size. I.e., largest shaft and smallest
hole.
Least Material Condition (LMC):
The condition where a size feature
contains the least amount of material
within the stated limits of size. I.e.,
smallest shaft and largest hole.
Tolerance: Difference between MMC
and LMC limits of a single dimension.
Allowance: Difference between the
MMC of two mating parts. (Minimum
clearance and maximum interference)
Basic Dimension: Nominal
dimension from which tolerances are
derived.
14. SIZE DIMENSION
MMC
LMC
ENVELOPE OF SIZE
(2.003)
(2.007)
ENVELOPE PRINCIPLE
LIMITS OF SIZELIMITS OF SIZE
A variation in form is allowed
between the least material
condition (LMC) and the
maximum material condition
(MMC).
Envelop Principle defines the
size and form relationships
between mating parts.
16. LIMITS OF SIZELIMITS OF SIZE
The actual size of the feature at
any cross section must be
within the size boundary.
ØMMC
ØLMC
17. No portion of the feature may
be outside a perfect form
barrier at maximum material
condition (MMC).
LIMITS OF SIZELIMITS OF SIZE
18. PARALLEL PLANES
PARALLEL PLANES PARALLEL PLANES CYLINDER ZONE
GEOMETRIC DIMENSIONING TOLERANCE ZONES
PARALLEL LINES PARALLEL LINES PARALLEL LINES
PARALLEL PLANES PARALLEL PLANES
Other Factors
I.e., Parallel Line Tolerance Zones
Other Factors
I.e., Parallel Line Tolerance Zones
20. Characteristics & Symbols
cont’d.
Characteristics & Symbols
cont’d.
– Maximum Material Condition MMC
– Regardless of Feature Size RFS
– Least Material Condition LMC
– Projected Tolerance Zone
– Diametrical (Cylindrical) Tolerance
Zone or Feature
– Basic, or Exact, Dimension
– Datum Feature Symbol
– Feature Control Frame
21. THE
GEOMETRIC SYMBOL
TOLERANCE INFORMATION
DATUM REFERENCES
FEATURE CONTROL FRAME
COMPARTMENT VARIABLES
CONNECTING WORDS
MUST BE WITHIN
OF THE FEATURE
RELATIVE TO
Feature Control FrameFeature Control Frame
22. Feature Control FrameFeature Control Frame
Uses feature control frames to
indicate tolerance
Reads as: The position of the
feature must be within a .003
diametrical tolerance zone at
maximum material condition
relative to datums A, B, and C.
23. Feature Control
Frame
Feature Control
Frame
Uses feature control frames to indicate
tolerance
Reads as: The position of the feature
must be within a .003 diametrical
tolerance zone at maximum material
condition relative to datums A at
maximum material condition and B.
24. The of the feature must be within a tolerance
zone.
The of the feature must be within a
tolerance zone at relative
to Datum .
The of the feature must be within a
tolerance zone relative to Datum .
The of the feature must be within a
zone at
relative to Datum .
The of the feature must be within a
tolerance zone relative to datums .
Reading Feature Control FramesReading Feature Control Frames
25. Placement of Feature
Control Frames
Placement of Feature
Control Frames
May be attached to a side, end
or corner of the symbol box to
an extension line.
Applied to surface.
Applied to axis
26. Placement of Feature
Control FramesCont’d.
Placement of Feature
Control FramesCont’d.
May be below or closely
adjacent to the dimension or
note pertaining to that feature.
Ø .500±.005
27. Basic DimensionBasic Dimension
A theoretically exact size, profile,
orientation, or location of a feature or
datum target, therefore, a basic
dimension is untoleranced.
Most often used with position,
angularity, and profile)
Basic dimensions have a rectangle
surrounding it.
1.000
30. Form FeaturesExamplesForm FeaturesExamples
Flatness as stated on
drawing: The flatness of the
feature must be within .06
tolerance zone.
.003
0.500 ±.005
.003
0.500 ±.005
Straightness applied to a flat surface: The
straightness of the feature must be within .003
tolerance zone.
31. Form FeaturesExamplesForm FeaturesExamples
Straightness applied to the surface of a
diameter: The straightness of the feature must
be within .003 tolerance zone.
.003
0.500
0.505∅
Straightness of an Axis at MMC: The derived
median line straightness of the feature must be
within a diametric zone of .030 at MMC.
.030
0.500
0.505∅ M∅
1.010
0.990
34. Activity 13Activity 13
Work on worksheets GD&T 1,
GD&T 2 #1 only, and GD&T 3
– (for GD&T 3 completely
dimension. ¼” grid.)
35. Features that Require
Datum Reference
Features that Require
Datum Reference
Orientation
– Perpendicularity
– Angularity
– Parallelism
Runout
– Circular Runout
– Total Runout
Location
– Position
– Concentricity
– Symmetry
36. DatumDatum
Datums are features (points, axis,
and planes) on the object that are
used as reference surfaces from
which other measurements are
made. Used in designing, tooling,
manufacturing, inspecting, and
assembling components and sub-
assemblies.
– As you know, not every GD&T
feature requires a datum, i.e., Flat
1.000
37. Datums cont’d.Datums cont’d.
Features are identified with
respect to a datum.
Always start with the letter A
Do not use letters I, O, or Q
May use double letters AA,
BB, etc.
This information is located in
the feature control frame.
Datums on a drawing of a
part are represented using
the symbol shown below.
38. Datum Reference SymbolsDatum Reference Symbols
The datum feature symbol
identifies a surface or feature
of size as a datum.
A
ISO
A
ANSI
1982
ASME
A
1994
39. Placement of DatumsPlacement of Datums
Datums are generally placed on a feature, a
centerline, or a plane depending on how
dimensions need to be referenced.
A AOR
ASME 1994
A
ANSI 1982
Line up with arrow only when
the feature is a feature of
size and is being defined as
the datum
40. Placement of DatumsPlacement of Datums
Feature sizes, such as holes
Sometimes a feature has a
GD&T and is also a datum
Ø .500±.005
A
Ø .500±.005
A Ø .500±.005
41. 6 ROTATIONAL
6 LINEAR AND
FREEDOM
DEGREES OF
UP
DOWN
RIGHT
LEFT BACK
FRONT
UNRESTRICTED FREE
MOVEMENT IN SPACE
TWELVE DEGREES OF FREEDOMTWELVE DEGREES OF FREEDOM
43. Primary DatumPrimary Datum
A primary datum is selected
to provide functional
relationships, accessibility,
and repeatability.
– Functional Relationships
» A standardization of size is desired in
the manufacturing of a part.
» Consideration of how parts are
orientated to each other is very
important.
– For example, legos are made in a
standard size in order to lock into
place. A primary datum is chosen
to reference the location of the
mating features.
– Accessibility
» Does anything, such as, shafts, get in
the way?
44. Primary Datum cont’d.Primary Datum cont’d.
– Repeatability
For example, castings, sheet
metal, etc.
» The primary datum chosen must
insure precise measurements.
The surface established must
produce consistent
» Measurements when producing
many identical parts to meet
requirements specified.
45. FIRST DATUM ESTABLISHED
BY THREE POINTS (MIN)
CONTACT WITH SIMULATED
DATUM A
Primary DatumPrimary Datum
Restricts 6 degrees of freedom
46. Secondary &
Tertiary Datums
Secondary &
Tertiary Datums
All dimension may not be capable to
reference from the primary datum to
ensure functional relationships,
accessibility, and repeatability.
– Secondary Datum
» Secondary datums are produced
perpendicular to the primary datum so
measurements can be referenced from
them.
– Tertiary Datum
» This datum is always perpendicular to
both the primary and secondary datums
ensuring a fixed position from three
related parts.
47. SECOND DATUM
PLANE ESTABLISHED BY
TWO POINTS (MIN) CONTACT
WITH SIMULATED DATUM B
Secondary DatumSecondary Datum
Restricts 10 degrees of freedom.
48. Tertiary DatumTertiary Datum
Restricts 12 degrees of freedom.
90°
THIRD DATUM
PLANE ESTABLISHED
BY ONE POINT (MIN)
CONTACT WITH
SIMULATED DATUM C
MEASURING DIRECTIONS FOR
RELATED DIMENSIONS
53. PERPENDICULARITY:PERPENDICULARITY:
is the condition of a surface, center plane, or
axis at a right angle (90°) to a datum plane or
axis.
Ex:
The tolerance zone is the
space between the 2
parallel lines. They are
perpendicular to the
datum plane and spaced .
005 apart.
The perpendicularity of
this surface must be
within a .005 tolerance
zone relative to datum A.
56. 2.00±.01
.02 Tolerance
Practice ProblemPractice Problem
Without GD & T this
would be acceptable
2.00±.01
.02 Tolerance
.005 Tolerance
Zone
With GD & T the overall height may end
anywhere between the two blue planes. But the
bottom plane is restricted to the red tolerance
zone.
58. ANGULARITY:ANGULARITY:
is the condition of a surface, axis, or
median plane which is at a specific
angle (other than 90°) from a datum
plane or axis.
Can be applied to an axis at MMC.
Typically must have a basic
dimension.
The surface is at a
45º angle with a .
005 tolerance zone
relative to datum A.
59. ±0.01
PARALLELISM:PARALLELISM:
The condition of a surface or center plane
equidistant at all points from a datum plane, or
an axis.
The distance between the parallel lines, or
surfaces, is specified by the geometric
tolerance.
62. Maximum Material ConditionMaximum Material Condition
MMC
This is when part will weigh the
most.
– MMC for a shaft is the largest
allowable size.
» MMC of Ø0.240±.005?
– MMC for a hole is the smallest
allowable size.
» MMC of Ø0.250±.005?
Permits greater possible
tolerance as the part feature
sizes vary from their calculated
MMC
Ensures interchangeability
Used
– With interrelated features with
respect to location
– Size, such as, hole, slot, pin, etc.
63. Least Material ConditionLeast Material Condition
LMC
This is when part will weigh
the least.
– LMC for a shaft is the smallest
allowable size.
» LMC of Ø0.240±.005?
– LMC for a hole is the largest
allowable size.
» LMC of Ø0.250±.005?
64. Regardless of Feature SizeRegardless of Feature Size
RFS
Requires that the condition of
the material NOT be
considered.
This is used when the size
feature does not affect the
specified tolerance.
Valid only when applied to
features of size, such as
holes, slots, pins, etc., with
an axis or center plane.
66. Position TolerancePosition Tolerance
A position tolerance is the total
permissible variation in the location
of a feature about its exact true
position.
For cylindrical features, the
position tolerance zone is typically
a cylinder within which the axis of
the feature must lie.
For other features, the center plane
of the feature must fit in the space
between two parallel planes.
The exact position of the feature is
located with basic dimensions.
The position tolerance is typically
associated with the size tolerance
of the feature.
Datums are required.
67. Coordinate System PositionCoordinate System Position
Consider the following hole dimensioned with
coordinate dimensions:
The tolerance zone for the location of the hole
is as follows:
Several Problems:
– Two points, equidistant from true position may not
be accepted.
– Total tolerance diagonally is .014, which may be
more than was intended.
2.000
.750
68. Coordinate System PositionCoordinate System Position
Consider the following hole dimensioned with
coordinate dimensions:
The tolerance zone for the location (axis) of the
hole is as follows:
Several Problems:
– Two points, equidistant from true position may not
be accepted.
– Total tolerance diagonally is .014, which may be
more than was intended. (1.4 Xs >, 1.4*.010=.014)
2.000
.750
Center can be
anywhere along
the diagonal
line.
69. Position TolerancingPosition Tolerancing
Consider the same hole, but add
GD&T:
Now, overall tolerance zone is:
The actual center of the hole (axis) must lie in
the round tolerance zone. The same tolerance
is applied, regardless of the direction.
MMC =
.500 - .003 = .497
70. Bonus ToleranceBonus Tolerance
Here is the beauty of the system! The
specified tolerance was:
This means that the
tolerance is .010 if the
hole size is the MMC size,
or .497. If the hole is
bigger, we get a bonus
tolerance equal to the
difference between the
MMC size and the actual
size.
71. Bonus Tolerance ExampleBonus Tolerance Example
This system makes sense… the larger the
hole is, the more it can deviate from true
position and still fit in the mating condition!
Actual Hole Size Bonus Tol. Φ of Tol. Zone
Ø .497 (MMC) 0 .010
Ø .499 (.499 - .497 = .002) .002 (.010 + .002 = .012) .012
Ø .500 (.500 - .497 = .003) .003 (.010 + .003 = .013) .013
Ø .502 .005 .015
Ø .503 (LMC) .006 .016
Ø .504 ? ?
This means that
the tolerance is .
010 if the hole
size is the MMC
size, or .497. If the
hole is bigger, we
get a bonus
tolerance equal to
the difference
between the MMC
size and the
actual size.
.503
72. .497 = BONUS 0
TOL ZONE .010
.499 - .497 = BONUS .002
BONUS + TOL. ZONE = .012
Shaft
Hole
74. What if the tolerance had been specified as:
Since there is NO material modifier, the
tolerance is RFS, which stands for regardless
of feature size. This means that the position
tolerance is .010 at all times. There is no
bonus tolerance associated with this
specification.
VIRTUAL CONDITION: The worst case
boundary generated by the collective effects of
a size feature’s specified MMC or LMC
material condition and the specified geometric
tolerance.
GT = GEOMETRIC
TOLERANCE
75. PERPENDICULARITY Cont’d.
PERPENDICULARITY Cont’d.
Means “the hole (AXIS) must
be perpendicular within a
diametrical tolerance zone of .
010 at MMC relative to datum
A.”
Actual Hole
Size
Bonus
Tol.
Ø of Tol.
Zone
1.997
(MMC)
1.998
1.999
2.000
2.001
2.002
2.003
Vc =
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.
Foster’s text
Foster’s text
Why symbols?
The symbol has uniform meaning. A note can be stated inconsistently, with a possibility of misunderstanding.
Symbols are compact, quickly drawn, and can be placed on the drawing where the control applies
Symbols can be made by computer or with a template & retain legibility when reproduced.
Symbols provide international language. Notes may need to be translated if used in another country.