To help understand

the 3D annotations,

the book includes a

complete tutorial on

SOLIDWORKS MBD

�e book covers the changes and

improvements in the ASME Y14.5-2018

standard

Technical product documentation using ISO GPS - ASME GD&T standards

3

FOREWORD

Designers create perfect and ideal geometries through drawings or by means of Computer Aided Design systems, but unfortunately the real geometrical features of manufactured components are imperfect, in terms of form, size, orientation and location.Therefore, technicians, designers and engineers need a symbolic language that allows them to define, in a complete, clear and unambiguous way, the admissible variations, with respect to the ideal geometries, in order to guarantee functionality and assemblability, and to turn inspection into a scientifically controllable process.The Geometric Product Specification (GPS) and Geometrical Dimensioning and To-lerancing (GD&T) languages are the most powerful tools available to link the perfect geometrical world of models and drawings to the imperfect world of manufactured parts and assemblies.This book is intended for designers, process engineers and CMM operators, and it has the main purpose of presenting the ISO GPS rules and concepts. Moreover, the differences between ISO GPS and the American ASME Y14.5 standard are shown as a guide and reference for the drawing interpretation of the most common dimen-sioning and tolerancing notations.A complete SolidWorks MBD tutorial has been added to the appendix of this book: SOLIDWORKS Model Based Definition (MBD) is a drawingless manufacturing so-lution that is embedded inside a SOLIDWORKS user interface. It helps companies define, organise and publish product and manufacturing information (PMI) in a 3D format that complies with international standards.

The book covers the changes and improvements in the ASME Y14.5-2018 standard

The author, Professor Stefano Tornincasa, has carried out research activities for over thirty years in the field of functional design and geometric tolerances. He was President of the ADM Improve Association (Innovative Methods in PROduct design and deVElopment) from 2011 to 2015 and has published more than 180 national and international scientific papers.He is co-author of the best-selling book on Industrial Technical Drawing, which is currently adopted in the design courses of most Italian universities (E. Chirone, S. Tornincasa, Industrial Engineering Design, Volumes I and II, ed. Il capitello Torino).Professor Tornincasa has conducted training courses on GD&T in many of the main manufacturing companies in Italy, and it is from this activity that he has derived his skill and experience in functional design.His other research topics have been focused on product development, cycle innovation through digital models and virtual prototyping methodologies (PLM)

http://webd.polito.it/workbook/

Technical product documentation using ISO GPS - ASME GD&T standards

9

2. CLASSIFICATION AND INDICATION OF GEOMETRIC TOLERANCES

Putting o� the discussion of new rules pertaining to the GD&T methodology to the next section, it is here opportune to recall some basic de�nitions in the context of what is now de�ned, in the rules and in practice, as GPS, that is, Geometrical Product Speci�cation.

Figure 8 shows some basic concepts of ISO 14460/1, which is often referred to in the ISO 1101 standard as the de�nition of Integral and derived features.

Fig. 8. The ISO standard provides terms that allow an engineer to understand the impact of the drawing specifications on inspection. A nominal integral feature is a theoretically exact feature that has been defined in a technical drawing. A nominal derived feature is an axis that has been derived from one or more integral features. Extracted and associated features are parts of the inspection domain. An associated integral feature is an integral feature of a perfect form associated with the extracted integral feature. An associated derived feature is an axis or centerplane of a perfect form.

Drawing-solid model

Inspection elaboration Inspection

Manufacturing

Nominal integral feature

Associated derived feature

Extractedderived feature

Associated integral feature

Extracted integral feature

Real integral feature

Nominal derived feature (axis)

The integral surface is a surface or line on a feature. The derived feature is a centre point, median line or median surface derived from one or more integral features.

A modelled cylinder is an integral feature, while the cylinder axis is an abstract element that can be derived from the cylindrical geometry. A derived or integral feature can be either nominal or real (that is, the manufactured element). In metrology, through the use of a CMM measuring machine, the extracted feature (integral or derived, that is, an approximated representation of the real feature, which is acquired by extracting a �nite number of points) is obtained from the real (integral) feature. A perfect associated feature (a cylinder or the derived axis, which can be used, for example, as a Datum) can thus be obtained from the extracted features. Geometrical features can be found in three domains:

• the speci�cation domain, where several representations of the future workpiece are imaged by the designer;

• the workpiece domain, that is, the physical domain;

• the inspection domain, where a representation of a given workpiece is used through the sampling of the workpiece by measuring instruments.

Technical product documentation using ISO GPS - ASME GD&T standards

33

16,9

min

imum

di

stan

ce

44,2 maximum two-point distances

Envelope of perfect form(maximum cylinder)

Envelope of perfect form

Fig. 54. The envelope requirement in the ISO standard is indicated by means of a circled E, which is placed next to the tolerance dimension; the hole has a perfect form when all the local diameters are in the maximum material conditions, that is, 18 mm.

Fig. 52. Verification procedure of a shaft according to the envelope principle or ASME Rule#1. The minimum material condition is controlled by an external gauge (the measurement between two opposite points), while the maximum material condition is checked by means of an envelope of perfect form with MMC dimensions.

Fig. 53. Verification procedure of a hole according to the envelope principle. The minimum material condition is controlled by an internal gauge (measured between two opposite points), while the maximum material condition is checked by means of a pin with the MMC dimensions.

appropriate in the case of mating, may be restrictive for all the other geometrical features, and may make it necessary, in the latter case, to furnish an indication of exception (the ASME standards have introduced the È symbol, see Fig. 55), with the consequence of a source of ambiguity being created as it is not possible to be certain that the absence

of such an indication depends on the choices of the designer or rather on an oversight within a complex technical document. Apart from this problem, the verification of the envelope principle, which requires the use of functional gauges1 or controls carried out by means of measurement machines that have

ISOdrawing

ASMEdrawing

Fig. 55. If one wishes to apply the independency principle in ASME drawings, it is necessary to insert the independence symbol I next to the dimension.

1Gage in ASME

The ASME Y14.5 standard makes a distinction between the concept of a datum feature, a datum and a datum feature simulator1 A datum is an abstract geometrical feature (point, axis or plane from which a dimensional measurement is made), which represents the perfect counterpart of a datum feature (e. g. an ideal plane or the axis of the perfect geometrical counterpart). The simulated datums are conceptually perfect (physically almost perfect), and they represent a bridge between the imperfect real world of datum features and the perfect imaginary world of datums. Ultimately, it is opportune to distinguish between the real datum feature of the workpiece (named datum feature) and the datum, the equivalent theoretical datum (plane, axis or centerplane), simulated by the associated inspection or manufacturing equipment.

The datum system of a tool machine is shown in Figure 85: the production equipment has the duty of aligning the features of the workpiece with the datums of the machine (for example, datum feature A is aligned with the clamping machine and datum feature B is made to coincide

datumfeature A

datumfeature B

Fig. 85. No datums exist on a workpiece but they are simulated by the datum feature system of the tool machine.

1 In the ASME Y14.5:2018 the term “theoretical datum feature simulator” was replaced with “true geometric counterpart”

Technical product documentation using ISO GPS - ASME GD&T standards

47

Datum system taken from two cylinders and a plane

1. first associated feature without a constraint2. second associated feature with a perpendicularity constraint from the first

associated feature3. third associated feature with a perpendicularity constraint from the first

associated feature (and parallelism constraint from the second one)

Resulting datum system4. plane which is the first associated feature5. point of intersection between the plane and the axis of the second associated

feature6. straight line which is the intersection between the associated plane and the

plane containing the two axes

In the ASME Y14.5:2018 the term “theoretical datum feature simulator” was replaced with “true geometric counterpart”

74

THE STRAIGHTNESS TOLERANCE IN THE ASME STANDARD

By default, the ASME Y14.5 standard applies the envelope requirement, and the rule shown in Figure 164 therefore applies. However, it is necessary to pay particular attention, because whenever the straightness tolerance is applied to a derived median line, Rule #1 is no longer applicable, that is, the component does not have a perfect form at the maximum material (and the rule in Figure 165 is therefore valid). Figure 170 shows, for the case of the shaft in Figure 165, the concept of derived median line, obtained from the set of central points of the singular perpendicular sections of the axis of the smallest restricted cylinder: the derived median line should fall within a cylinder centred on the nominal axis of an envelope of perfect form. The configuration indicated in Figure 167 is called “virtual condition”, and it defines the fixed size of the functional gauge that should be used for the verification of a straightness error (Fig. 171).

THE STRAIGHTNESS TOLERANCE IN

centre points of each cross section

axis AME

derived median linestraightness tolerance zone diameter 0,04

Fig. 171. Whenever straightness is specified on an MMC basis, functional gauging techniques may be used.

In the ASME Y14.5:2018 the supplementary geometry in the annotated model avoids the use of the intersection plane of the ISO standard

Fig. 170. The concept of derived median line for the case of a shaft, obtained from a set of central points of the single perpendicular points of the axis of the smallest restricted cylinder (Actual Mating Envelope): the derived median line should fall within a cylinder centred on the nominal axis of an envelope of perfect form.

FlatnessFlatness represents the condition of a surface which has all its points

belonging to the same plane: the �atness error is constituted by the deviation of the real surface points from the plane.

A �atness tolerance speci�es a three-dimensional zone, determined by two parallel planes with a distance that is equal to the �atness control tolerance value. One of the two planes of the tolerance zone is orientated by the highest points of the surface, while the other plane is parallel to the �rst and o�set by the �atness tolerance value.

derived median line

derived median line

Virtual condition

Virtual condition

Virtual condition

the part produced with the actual low limit size (LMC) permits the straightness to be increased to 0,24

LMSgauge

gauge

gauge

113

As pointed out in the previous sections, the ISO standard is defined as “CMM Friendly”, that is, the preferred control system is the coordinate measurement machine. The ASME standard is based on the idea of specifying the geometrically perfect zones within which the real surfaces should fall. This is often indicated as a preference for “hard gauging”, which means that it is possible to construct functional gauges that represent a physical representation of the tolerance zone. A functional gauge basically represents the materialisation of the feature that has to be mated (worst case) according to the specifications indicated on the drawing.

In short, a gauge is nothing more than a simulated physical datum feature that allows the relationships between geometrical and dimensional errors to be verified at the same time, and the effect of an increase in tolerance, due to a maximum material modifier applied to either the feature itself (bonus) or to the datums (called shift or MMB), to be foreseen. Generally, the tolerance on a gauge is about 10% of the tolerance that has to be controlled, with temperature conditions of 20° and humidity no higher than 45%. If a functional gauge is mated with the piece that has to be controlled, it is possible to be almost absolutely certain of the assembly with the mating counterpart.

CONTROL WITH FUNCTIONAL GAUGES

Fig. 287. The two pattern tolerance zones are contained

in simultaneous tolerance zone frameworks related to the same DRF, thus they are

basically aligned.

simultaneously by means of a pattern specification, using tolerance zone pattern modifiers CZ, CZR or SIMn (fig. 288).

The use of the concept of “simultaneous requirement” transforms a set of more than one geometrical specification into a combined specification, i.e. a pattern specification.

Fig. 288. In order to obtain the same functional requirements of the previous figure, the ISO standard uses the modifiers CZ and SIM1.

Technical product documentation using ISO GPS - ASME GD&T standards

135

B, resulting in only one pattern specification. The tolerance zone pattern (combined zone) is composed of twenty-four cylindrical zones of diameter 0,6 mm with orientation constraint (parallel between them and perpendicular to datum A) and with location

constraint between them (at 16 mm [24 mm between the groups] apart in a horizontal direction and 12 mm [28 mm between the groups] apart in vertical direction and constrained from datum B and C to a distance of 12 mm).

Alternative indication with the same meaning as in previous figure

170

Designed withDesigned with

General profile tolerance properties are thus defi-ned, and when finished, a “Part1” feature with a surface profile associated to it will appear in the DimXpert manager feature based tree.In this case, an important best practice that should

be followed is to add a note to define an all-o-ver general profile tolerance: this can easily be accomplished by adding a note and clicking on the “Insert DimXpert general profile tolerance” in the note property manager (Fig. 26).

It can be noted that, even though basic dimen-sions have not been created, all the manufactu-ring features are completely defined; this is because, in model-based processes, downstre-am applications, such as CAM or inspection software, can automatically derive this informa-tion from the PMI.If needed, it is possible to display the basic dimensions by making DimXpertmanager as an annotation based tree, and by right clicking on a positional tolerance and selecting “recreate ba-sic dim” from the context menu.As shown in Fig. 27, in this way, basic dimen-sions will be created with respect to the datum refe-rence frame.

Fig. 27

Fig. 26

OTHER GD&T TOOLS

SOLIDWORKS Model Based definition includes other tools that can be used to dimension tolerances to tolerance a part in compliance with ASME standards, such as: Manual basic location dimension Manual basic size dimension Moveable datum targets

These tools can be found in the MBD tab in the command manager.

172

Designed withDesigned with

Select three datum features, as shown in Fig. 5, and the “All fe-atures” option will be selected in the “Scope” pane. Finally, click on OK in the DimXpertManager.

The model will be dimensioned with respect to the 3 datums, and if the tolerance status is checked, a green colour will indicate that all the manufacturing features have been defined completely (Fig. 6).It is possible to make a general

Fig. 6

Fig. 8

Fig. 7

tolerance value explicit on certain dimensions by clicking on a di-mension and selecting “General with tolerance” in the dimension property manager (Fig. 7).

Instead of showing explicit tole-rances, an alternative approach could be to insert a general to-lerance table in the model. This can be done by choosing Insert g Tables g General tolerance (Fig. 8).

By using the concepts learnt in the previous sections, a 3D View may then be created to show the part and the table (Fig. 9).

As can be noted in Fig. 6, the au-to-dimensioning process is able to completely define all the ma-nufacturing features, but being an automated process, it cannot replace a designer’s experience in applying GD&T best practices. It is therefore suggested to use a combination of manual and auto-matic dimensioning to obtain the best results.Before illustrating an example of this approach, all the annota-tions should be deleted: this can easily be achieved by deleting the dimensioning scheme in the DimXpertmanager. It is sufficient to right-click on the part name, then select “delete” from the con-text menu (Fig. 10). If the mes-sage “Do you want to delete all DimXpert features, dimensions, and tolerances?” appears, select “Yes”.

Fig. 5

FOREWORD ............................................................................................................................................................................................................PAGE 31. INTRODUCTION ......................................................................................................................................................................................................... 42. CLASSIFICATION AND INDICATION OF GEOMETRIC TOLERANCES ..................................................................... 93. DIMENSIONING WITH GEOMETRICAL TOLERANCES .......................................................................................................184. THE GD&T LANGUAGE ACCORDING TO THE ISO AND ASME STANDARDS ................................................22

The fundamental ISO 8015 standard ...................................................................................................................................................................25General geometrical tolerances ................................................................................................................................................................................29The main differences between the ISO GPS and ASME GD&T standards ..................................................................35

5. INTERDEPENDENCE BETWEEN THE SIZE AND FORM ......................................................................................................37Maximum material condition .......................................................................................................................................................................................37Least material conditions ..................................................................................................................................................................................................40Virtual condition ..........................................................................................................................................................................................................................40

6. DATUMS ..........................................................................................................................................................................................................................42Indication of the datum features .............................................................................................................................................................................44Terms and definition in ISO 5459 .............................................................................................................................................................................45Location of a workpiece in a datum reference frame ....................................................................................................................50Selection of the datum features ................................................................................................................................................................................51Types of datums ...........................................................................................................................................................................................................................54Datum features referenced at MMR and LMR (Size datum) .....................................................................................................57Customised datum reference frame .....................................................................................................................................................................58Examples of other modifiers used to indicate datums ...................................................................................................................61Datum targets.................................................................................................................................................................................................................................63Contacting feature ....................................................................................................................................................................................................................67

7. FORM TOLERANCES ............................................................................................................................................................................................70Straightness tolerance ..........................................................................................................................................................................................................70Flatness...................................................................................................................................................................................................................................................74Roundness ..........................................................................................................................................................................................................................................78Cylindricity .........................................................................................................................................................................................................................................79

8. ORIENTATION TOLERANCES ......................................................................................................................................................................81Parallelism ...........................................................................................................................................................................................................................................81Perpendicularity ..........................................................................................................................................................................................................................84Angularity ...........................................................................................................................................................................................................................................87

9. LOCATION TOLERANCES ................................................................................................................................................................................91Position tolerances ...................................................................................................................................................................................................................91Position tolerance applied to median surfaces .......................................................................................................................................95Effects of Specifying the MMR Modifier .......................................................................................................................................................107Concentricity ................................................................................................................................................................................................................................109Symmetry ........................................................................................................................................................................................................................................110

10. PROFILE TOLERANCES ...............................................................................................................................................................................116ISO 5458:2018. Pattern and combined geometrical specification ................................................................................123

11. RUN-OUT TOLERANCES ............................................................................................................................................................................124 Circular run-out .......................................................................................................................................................................................................................125 Total run-out ...............................................................................................................................................................................................................................126

12. GEOMETRICAL PRODUCT SPECIFICATION FOR NON-RIGID PARTS ...........................................................130 ISO 5458:2018. Multi-level single indicator pattern specification ........................................................................134Tolerancing of a cone .........................................................................................................................................................................................................136

1. Introduction to SOLIDWORKS MBD ........................................................................................................................................1382. The first step towards MBD: making a 3D model the master by leveraging

on modelling dimensions with annotation views .................................................................................................1403. Using DimXpert for coordinate tolerancing .................................................................................................................1474. 3D Views ...................................................................................................................................................................................................................1585. GD&T with DimXpert ................................................................................................................................................................................1646. Preparing the model and reading manufacturing information ...........................................................1717. Leveraging on PMI .......................................................................................................................................................................................178INDEX ....................................................................................................................................................................................................................................182

INDEX

AACS (Any Cross Section);

61; 109Actual Mating Envelope,

AME; 48All around; 14All over; 14Altered default GPS

speci�cation; 25Angularity; 87ASME BSC (Basic); 69ASME Y14.5 standard; 23ASME-ISO comparison; 37Associated feature; 9Association

methodology; 61Axis methodology; 96

BBasic Dimension; 14Bi-directional tolerance

of position; 107Bonus; 38

CCenterplanes; 54CF symbol, see Contacting

featureCircular run-out; 124, 125Circularity,

see Roundness; 78Classi�cation

of Geometrical Tolerances.; 11

Coaxiality; 109Collection plane; 17Combined zone; 15Common datum; 55Common Zone, see

Combined Zone; 15, 18Complementary

standard; 24Composite Position

Tolerancing; 103Composite

pro�le feature; 120Composite tolerance

frame; 73Computer Aided Design; 5Concentricity; 109Concentricity ASME; 111

Cone tolerancing; 136Contacting feature; 67Coordinate dimensioning; 6Coplanar Surfaces; 121Customised datum

reference frame; 58Cylindricity; 79CZ (Combined Zone); 118

DDatum; 42Datum axis; 44Datum conical surfaces; 57Datum feature simulator; 47Datum features; 43Datum pattern of holes; 55Datum targets; 63Default principle; 28Degrees of freedom of a

workpiece; 50Derived feature; 9Derived median line; 74DRF (Datum Reference

Frame); 50Duality principle; 28, 35DV (distance variable; 56

EEnvelope requirement; 32Extracted derived

feature; 9

FFeature of Size; 19Feature-Relating Tolerance

Zone Framework; 111Filter speci�cation; 79Fixed fastener formula; 100Flatness; 74Flatness (ASME); 77Floating fastener formula;

99Form tolerances; 10; 70Free State condition; 130Functional dimensioning; 4Functional gauge; 68, 113Functional gauging

techniques; 74Functional limits; 28Fundamental standard; 24

GGage; 33, 113Gauges; 33Gaussian (G) method; 61Gaussian circle; 72Gaussian dimensioning

concept; 35Gaussian interpolation; 72GD&T; 5; 22General geometrical

tolerances; 29General speci�cation

principle; 29General standard; 24Geometrical Casting

Tolerance Grades; 31Geometrical tolerances

Summary chart; 137GPS; 9; 22GPS Matrix Model; 23

IIndependency principle; 25Indication of a derived

feature; 13Indication of the

datum features; 44Inspecting

concentricity; 111Inspecting �atness; 76Inspection of roundness; 79Integral; 9Integral feature,

indication; 13Intersection plane; 15Invocation principle; 26ISO 10579-NR; 130ISO 1101; 9, 24ISO 14638; 24ISO 2768/2; 29ISO 5458:2018; 123, 134ISO 5459; 43, 45, 60ISO 8015; 25ISO 8062-3; 31ISO/TC 213; 23

LLeast Material Condition

(LMC); 32, 40Least Material

Requirement, LMR; 40

Least Material Size (LMS); 99

Least Material Virtual Condition, LMVC; 40

Least Material Virtual Size, LMVS; 40

LMB Least Material Boundary; 57

Location tolerances; 10; 91

MMaximum Material

Boundary (MMB); 63Maximum Material

Requirement, (MMR); 37Maximum Material

Size (MMS); 41Maximum Material Virtual

Condition, MMVC; 40Maximum Material

Virtual Size, LMVS; 40Maximun Material

Condition (MMC); 32Minimax Chebyshev; 18Minimum circumscribed

association; 80Minimum zone criterion

(Chebyshev); 79MMB Maximum Material

Boundary; 57MMR Applicability; 39modi�er T; 18modi�er U; 121modi�er X; 18

NNon Rigid part; 130

OOrder of the datums; 51Orientation plane; 16Orientation

tolerances; 10, 81OZ symbol; 119

PParallelism; 81Pattern-Locating Tolerance

Zone Framework; 111Pattern speci�cation; 123,

134

ANALITIC INDEX

184

Analitic index

Perpendicularity; 84Position tolerance ASME; 111Position tolerance median

surfaces; 95Position tolerances; 91Position tolerances

calculation; 98Pro�le; 116, 117Pro�le any line; 118Pro�le dynamic; 122Pro�le tolerances; 118Projected

tolerance zone; 100, 101

QQuali�cation of the datum

features; 52

RReciprocity; 105

Reciprocity requirement (RPR); 106

Regardless of Feature Size, RFS; 37

Related actual mating envelope; 49

Restraint Note; 132Rigid workpiece

principle; 28RMB, Regardless of

Material Boundary; 57Roundness; 78Rule#1; 32Runout tolerances; 10Run-out tolerances; 124

SSelecting modi�ers for

position tolerances.; 95Selection of the

datum features; 51

SF (Fixed Size); 69Shift; 106Simulated datums; 47Simultaneous

requirement; 18, 112Size datum; 57Straightness; 70Straightness (ASME); 74Symmetry; 110, 112SZ (Separate Zone); 18, 96

TTangent plane; 18, 129Taylor’s principle Rule#1; 32Theoretical envelope

plane; 43Theoretically Exact

Dimensions (TED); 14, 91Tolerance frame; 13Theoretically

exact feature (TEF); 119

Tolerance indicator; 12 Tolerance,

summary chart; 137Total run- out; 122, 124

UUF (United Feature); 18, 61UZ symbol; 119

VVariable Angle (VA); 136Virtual boundary condition

methodology; 96Virtual condition; 40

ZZero tolerance; 105

REFERENCES

(1) Georg Henzold, Geometrical Dimensioning and Tolerancing for Design, Manufacturing and Inspection: A Handbook for Geometrical Product Speci�cation using ISO and ASME standards, Butterworth-Heinemann, 2006.

(2) E. Chirone, S. Tornincasa, Disegno tecnico Industriale, vol. I e II, ed. Il capitello, 2018.

(3) The American Society of Mechanical Engineers, Dimensioning and Tolerancing ASME Y14.5 2009, 2009.

(4) Alex Krulikowski, Advanced Concepts of GD&T Textbook Based on ASME Y14.5M - 1994, E�ective Training Inc, 1999.

(5) Bryan R. Fischer, The Journeyman’s Guide to Geometric Dimensioning and Tolerancing: GD&T for the New Millennium, Advanced Dimensional Management Press, 2009.

(6) Alex Krulikowski, Fundamentals of GD&T Self-Study Workbook 2th ed., E�ective Training Inc, 1997.

(7) Don Day, The GD&T Hierarchy (Y14.5 2009), Tec-Ease, Inc., 2009.

(8) Alex Krulikowski, Alex Krulikowski’s ISO Geometrical Tolerancing Guide, E�ective Training Inc., 2010.

(9) Edward Morse, Tolerancing Standards: A Comparison, Quality Magazine, 2016.

(10) Gunter E�enberger, Geometrical Product Speci�cations (GPS) - Consequences on the Tolerancing of Features of Size, TEQ Training & Consulting GmbH, 2013.

(11) International Standards Organization, ISO 8015:2011 Geometrical product speci�cations (GPS) - Fundamentals - Concepts, principles and rules, International Standards Organization, 2011.

(12) International Standards Organization, ISO 1101:2017 - Geometrical product speci�cations (GPS) - Geometrical tolerancing - Tolerances of form, orientation, location and run-out, International Standards Organization, 2017.

(13) International Standards Organization, ISO 5459:2011 Geometrical product speci�cations (GPS) - Geometrical tolerancing - Datums and datum systems, International Standards Organization, 2011.

(14) Alex Krulikowski, ISO GPS Ultimate Pocket Guide, E�ective Training Inc., 2015.