Visualization and Engineering Design Graphics with Augmented Reality Third Edition [3rd Edition] 9781630572693, 1630572691

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Visualization and

engineering Design urapnics with Augmented Reality Jorge Dorribo Camba, Jeffrey Otey. Manuel Contero, Mariano Alcafiz

Third Edition

‘J

RY / ID

PUBLICATIONS

i

,

Better Textbooks. Lower Prices.

www. SDCpoublicatians.com

Start

the program

4umch

or

the

Do MOT

VOU

COVER THE

ALIGMENTED REALITY

MARKERS

IT'S ABCOMMENDED AVOIDING EXTREME LIGHTING CONDITIONS CAN ADjUST THE CAMERA SETTINGS FRDM THE SETUP SOFTWARE

Augmented Reality WHAT IS AUGMENTED REALITY? Avamented Reality is a technology that superimposes a computerGenerated image onto a user's view of the real world in real-time

The

augmented

reality software

that

comes

with

this

book,

Visualization and EDC with AR, helps you leam 30 visualization skills by combining virtual 3D models with real-time video, The result is @ Unique experience: an interactive world that makes the leaming

process faster and more engaging, This book represents a new way of adapting traditional engineering graphics materials to modenn times.

ABOUT THE SOFTWARE

VISUALIZATION

ANDO

EDG

WITH

AR

This textbook comes with augmented reality computer software and

apps, called Visualization and EDG with AR. Visualization and EDG

De pictorial a 90 cbpert being aiperinpoied

with OR is designed to be used while you progress through the text The Visualization and EDG with AR software and apps, in conjunction

ontop of a book uning augmented reality

aw

with the book, allow you to visualize the models desrribed in the text in full 30. Versions of the Viswalization and EOG with AR software are available for both the Mac and PC operating systems, Visualization

and EOG with AR apps are available for both Apple® i0S and Android® smartphones and tablets.

After you install the Visualization and EDG with AR software or app onto your device, place the markers located throughout the book along with the lange primary marker found at the front of this book, so they are both wisible to your device's camera. A 30 model will appear on your Screen, sup@rimposed on top of the lange marker. As you rotate and move the marker the 3D model will follow your movements. allowing you to manipulate the 30 model in real time,

Visualization and EDC with AR Logo RIED Fe

aa

Installation INSTALLING THE APPS Visualization and EDG with AR for Apple® iOS devices can be downloaded from the Apple® App Store. Visualization and EDC with AR for Android devices is available from the Google* Alay Store. If your device has an app installed that can read OR codes you can use it to scan the OR code to the left (see Ficure 3) and youwill be redirected tO The COMeCT apo for your device, Otherwise, visit your devices corresponding app store and search for Visualization and EDG with AR. Visualization and EDC with AR was developed by the Institute for Research and Innovation in Bioengineering Viuiaization ao OF

cocie

amd EDG

wath

AR

INSTALLING THE SOFTWARE Start by downloading the software installer from the publisher's web Site at viii Socpublications.com/ Downloads; q78-1-63057-269-3/ oF

by using the site search and browsing to the book's details page. After downloading the version of the software installer that matches your operating system, double click the software installer, The software installer window will appearand walk you through a series of steps to Complete the installation

USING THE 30 MODELS In acid ition to the Viswalization and EDG with AR sotware and Apps,

SOUDWORKS®

files of the models used throughout the book are

available. These files are available for download from the publisher's website at SDCpublications.com, In addition, STL files have been

provided sa the modets can be opened using your solid modeling CAD package of choice or printed using a 30 printer,

Using Visualization and EDG with AR 1.

LAUNCH VISUALIZATION AND

Once you have the

Visualization and EDG

EDG WITH AR with AR

software or app

installed on your device you wall need to start the application. To start the software, locate and select the Visualization and EDG with AR

icon. If you are using the Visualization and EDG with AR software ona Mac or PC you will need to have a camera connected for the software tovork conmecth, The camera can be a built-in oranexternal webcam If you are BiVen two you IF you Choosing

wing the Visualization and EDG with AR App, you will be wewineg choices when the software loads, The app will ask vant to view the 30 models ‘Without AR’ or With 4R Without AR’ will allow you to wiew the 30 models without

augmented reality. Choosing

With AR’ will allow you to view the 30

Mode!s using auEMented reality

2.

SCAN THE MARKERS

IN THE BOOK

Starting in chapter two, at the top of many of the pages are markers vehich look like a series of black and white squares. Place the book so your device's camera can see the markers on the page. Scanning the

markers tells the software what pace you are on, soit knows what 30 model to load. When the software successfully detects the marker the comespondine chapter and section title will appear at the top of the Screen

3,

VIEW THE 3D MODEL

Piace the lange marker located at the front of this book so that it is visible to your device's camera. A 30 model will appear on your screen superimposed on top of the marker. You can now interact with the 30 model

As you rotate and move the marker the 3D model

will also

follow your movements, allowing you to manipulate the 30 model in Depiction of ire Vis ualizanon and BOG math 4h sottare muse

real the (see Figure 4) Fe

aa

roubleshooting if you have trouble getting the software or apps to recognize the markers, review the following tips: * Be sure the marher is flat. If the marker is curved or bent the softwane might not cormectly recogmine its shape: * Make sure your device's camera can “see" the entire marker. If the markers are covered, or not entirely visible to the carnera, the 30 model will not display Additionally, it Is necessary to keep a small white margin around the marker. * You may need to adjust your camera's distance from the marker Try moving the marker closer or farther away from your device's Camera. in some cases moving the marker closer or farther away may make it easier for the software to detect it. Try adjusting the angle of the marker to the camera, Adjust the marker so that it’s perfectly square in the camera's view * Make sure your device's camera is focused on the marber, If the

camera is out of focus the marker will appear blurry and the software will not be able to recognize it. Check the lighting. If the iehting is too bright or too dark the software will hawea hard time recognizing the marker. You may be able to adjust your camera's settings or the lighting in your

room te correct this

Visualization and

Engineering Design Graphics with Augmented Reality

Copayrigtit ©2009 Jorge Doribo Camba jeffrey Otey. Manuel Contero, and Mariang Alradiiz Allnights reserved. This document may not fe copied paotncopaed. reproduced,

‘TRnITed, oF franca ted in. any form orfior arry purpose without the express written Comment of the publisher 500 Publications and the authors, isa winatian of Lintted States copyright laws to male copies in any fon or mena

of the contents of this book for either commercial or educational purposes without enpeis weltten perniision. Trademarks:

Windows is a registered trademark of Microsoft Corporation in the Uneted States and other courtres. Agpin, Pod, hone, Pack. Mar 05 and iOS are registered trademarics of Apple Inc. Android is a trademark of Googie inc

Evarminatian Cogaes Books reneved a3 examination mnpies ane for

view puspoies only and may not be

made available for student use. Resale of examination copes is poohibited.

Ebectroetc Files: Any chronic fies. assoc lated with this hope are icensedto the orginal user arly. These files may not be transfered ta anyother party. (Ceecagrnedd bry Beneter wan bleneteccomn

Published by: ‘Stephen Schrott SDC Publcations

P.O. Box 1334 Mission KS Gazz (ora) 260-2hb4

wan SDC publicatines com BM ISBN: s78-1-b3057-205-3

PUBLICATIONS

Visualization and Engineering Design Graphics with Augmented Reality Jonce DorRRipo CAMBA JEFFREY OTEY MANUEL CONTERO MARIANO ALCANIZ

INTRODUCTION

9

CHAPTER 1. SKETCHING AND LETTERING

7

1. INTRODUCTION

18

2. SKETCHING

19

A. SRETCHING TOOLS

8, SHETCHING TECHNIQUES

3, LETTERING

28

4, EXERCISES

30

CHAPTER 2. ORTHOGRAPHIC PROJECTION

Table of Contents

1 INTROOUCTION

43

———_________44

2. ORTHOGRAPHIC PROJECTION

4s

3. PROJECTION METHODS

4a?

4, ALPHABET OF LINES

48

5. VIEW SELECTION

ag

6. CONVENTIONAL PRACTICES

53

7, FORESHORTENING

54

&. ORTHOGRAPHIC PROJECTION AlDS

55

9, EXERCISES

S?

CHAPTER

3. PICTORIALS

8?

1. INTRODUCTION

a8

2. PROJECTIONS

89

3. GENERAL

PRACTICES

FOR

PICTORIAL

DRAWINGS

a1

4, OBLIQUE PROJECTIONS A. SRETCHING

DeLgue

9 DeawinGs

5. AXONOMETRIC PROJECTIONS

96

A. BOMETAIC PROJECTION B. SMETCHING ISOMETRIC DRAWINGS c. Deaetric Peopectros 0. TRIMETAIC PROyecTION

6, PERSPECTIVE PROJECTION

105

4. SMETCHING PERSPECTIVE DRAWINGS

7. EXERCISES CHAPTER 4. SECTIONAL VIEWS 1. INTRODUCTION

2. SECTIONAL VIEWS

111 141 -M2

a

4. THE CUTTIANG PLANE

B. HATCHING 3. TYPES OF SECTIONAL VIEWS A. B. Cc. Db, E.

FULL SECTIONS OFFSET SECTIONS HALF SECTIONS Rewo.veo ano REMOVED SECTIONS BaokEN-Our SECTIONS

we

&. GENERAL TOLERANCES

4, GENERAL AND CONVENTIONAL SECTIONING

PRACTICES 4.

UNMATCHED

153

B. LINEAR TOLERANCES TYPES oF FITS

O, i,

FEATURES

8. CONVENTIONAL ROTATIONS

5. BROKEN VIEWS AND CONVENTIONAL BREAKS 158 6. EXERCISES CHAPTER 5. AUXILIARY VIEWS

161 183

1. INTRODUCTION 1B4 2. AUMILIARY VIEWS AND PLANES 185 3. GENERAL PRACTICES FOR AUXILIARY VIEWS 186 4, CONSTRUCTION OF AUXILIARY VIEWS 5. EXERCISES CHAPTER 6. DIMENSIONING 1. INTRODUCTION 2. DIMENSIONING TERMINOLOGY 3, GENERAL DIMENSIONING RULES

188 795 Z15 216 217 z18

A. DIMENSIONING STYLES

EFS

Froeieanrmoenr w

. DIMENSIONING SPACING

BASPC-HOLE AND BAsiC-SHAFT SYSTEMS STANGAD FITS

4, GEOMETRIC TOLERANCES A. TOLERAMCES OF FORM

280

&. TOLERANCES OF PROFILE

C. TOLERANCES OF ORIENTATION D. TOLERANCES OF LOCATION E. TOLERANCES OF RussouT 5, EXERCISES ————___________}gg

CHAPTER 8. THREADEO FASTENERS

309

1, INTRODUCTION 2. FASTENERS

370 an

3a. THREADED FASTENERS

az

4, BASIC DEFINITIONS ————__312 5. THREAD CHARACTERISTICS a.

DIRECTION

B.

LEAD

—

a3

¢. FORM

. USE or Leanens . DIMENSIONS OUTSIDE WiEWS . DIMENSIONS BETWEEN VIEWS . OMission OF DIMENSION FEATURES . CONVENTIONAL WS. BASEL Ime DIMENSIONS

BD. SERIES E. O“L455 oF AT

6, THREAD SPECIFICATION A. THREAD SvMBOLS

317

B. THREAD NOTES

. Do Not Cadss Dimension LINES

7, HEAD AND DRIVE TYPES

Do Wot Ove R-Deaen sion

az

8, BOLTS AND SCREWS ——__________a2 9, NUTS 373

Use oF REFERENCE DIMENSIONS . Do Mot DIMENSION TO HIDDEN LINES . Do Nor Dimension To T-joInTS . DIMENSIONING ANGLED FEATURES

10. UNTHRESOED FASTENERS

—

7. EXERCISES

324

95

anvnpe

DOZ2

. DIMENSIONING CRELES

. DIMENSIONING HOLES AMD CYLINDERS

CHAPTER 9. WORKING DRAWINGS

. DIMENSIONING OBJECTS WITH ROUNDED ENDS . REPETITIVE FEATURES . CHAMPERS. FILLETS, AND ROUNDS . CENERAL NOTES

1. INTRODUCTION—_____________336 2. PAPER AND LAYOUT 337 3. STRUCTURE OF 4 SET OF WORKING ORAWINGS ———________________438

. FinisHiED SUAFACES

4, MACHINED HOLES ————___738 5. EXERCISES 245 CHAPTER 7. TOLERANCES 1. INTRODUCTION 2. TOLERANCES

335

265 366 267

3. DIMENSIONAL TOLERANCES ——_—268

A.

ASSEMBLY DRAWINGS

B. DETAIL Daawines C. STANDARD PART NoTes

4, EXERCISES APPENDIX I. TOLERANCE TABLES Il. THREAD TABLES

347 369 370 281

V Introduction

Introduction Graphical communication has been used for hundreds of years to document ideas and designs, From prehistoric paintings, to architec tural drawings in ancient Greece and Rome, to Da Vinel's famous il lustiations during the Renaissance, to the development of descriptive geometry and projection techniques, to computer graphics and para-

metric modeling software, to virtual and augmented reality, drawings and graphical information have been used with the purpose of communicating ideas, Technical communication is a useful tool to transfer knowledge ina collaborative environment, and to convince others of the quality of a

design in onder to obtain permits, patents, or funding. Communica ton in engineering happens verbally, in the form of meetings. presen-

tations, disqussions, or conversations; and in writing, in the form of proposals, reports, technical memorandums, notes. emails, and other decuments. However, many engineering ideas are simply too corm

plex to be communicated with words and require the use of graphic representations. Traditionally, engineering communication

has primarily taken

the

form of drawings, which can be reproduced and shared at low cost.

Currently, drawings can be converted to electronic formats and delvered to others almost instantaneously regardless of their location These drawines can then be utilized by other members of the team to

construct or manufacture the final product Engineering drawings are used in all engineering Relds and will follow industry or Organizational quidelines in their creation and application.

As an example, machanical engineers will ust drawings to document an improved design for brake pads, while structural engineers will use a Set of house plans, drawn by anhitects, to properly design beams

and joists.

Regardless of the technical field, various rules govern

many facets of graphical communication.

STANDARDS VS. CONVENTIONS Technical communication is driven by ules that ensure all parties understand a message clearly and unamibneuoushy. The terms “stan-

dards” and “conventions” are commonly used interchangeably, but

they have very explicit definitions, BoOvern an activity.

Standards are official rules that

They are established by various govemmental

and industrial organizations.

Examples include the distance from the

free throw line to the front of the rim in basketball (defined try FIBA) the asphalt content in roof shingles (defined by ASTM, formerly the

American Society for Testing and Materials), or the viscosity of 10MW20 motor of (Society of Automotive Engineers).

Conventions, on the

other hand, are practices or methods used so frequently and extensively that they become the most common approach used to accom plish certain tasks. In this case, there is not a formal document that defines the activity. but a general consensus about how the activity 6 performed, Conventions are also known as “industry standards” or

“de facto standards.” Examples of conventions include shaking with a fight hand when meeting someone, or common file formats used for engineering drawings.

eee

tia

The Engineering Design

Process

The Engineering Desien Process is a problem analysis mechanism

Problem Definition

that

incorporates

creativity,

the

scientific method,

mathematics,

and engineering principles in onder to solve a particular problem.

It

6 hormally represented a5 a cycle, in whith each step cari move the project forward, or revert to a previous stage (if problems need to be

Brainstorming

comected) before further, and more expensive, design steps are taken Variations of the design process are found across different industries, companies. and even problems.

Design and Analysis

|

Design Refinement

'

Design Implementation GERD

Wires engineering design process

Some traditional design processes

are linear, moving sequentially from one step to next. Others ane concurrent, where multiple steps are performed in paraliel,

The common stages of the engineering desian process include defin-

|

ing the Problem, brainstorming possible solutions, selecting pnelint-

nary desiens. development and analysis. refinement. and implemen-

|

tation (see Figure 1) DEFINE THE PROBLEM Defining or recognizing the problem is the first step of the design process. The problem must be clearly articulated, criteria and constraints must be identified, and decisions must be made as to what results will determine a successful outcome, At this stage, much informa-

tion is graphical in nature: sketches, preliminary calculations, tables,

charts, etc. Oftentimes, technical information is more easily understood and visualized when communicated in graphical form.

BRAINSTORMING In this stage of the design process, preliminary ideas and solutions

are listed. The amount of ideas is more important than the quality of each swegestion, To ensure successful brainstorming sessions in group settings, it is important that any value judement with regard

to the quality of any dea is withheld. Quality discemment wall occur in later stages, after a sufficient amount of ideas has been proposed.

Ideas are bypically accompanied with sketches (often with dimensions and notes) inorder to fully grasp their appeal and applicability,

can be originalor refinements of previous desiens,

Ideas

UOT

igre

ernety

Refined seetch and CAD monet

TZ

PRELIMINARY DESIGN After completion of the brainstorming stage, all ideas are evaluated Similarare Omplementary ideas are combined, ideas that donot

seem

promising are discarded, refined sketches are produced, and the functional relationships amone the various components of an idea are illustrated The best ideas are further developed, sketches are tumed into drawings using CAD

(see Ficure 2). and preliminary analysis may be per-

formed in order to separate the best ideas from those that fall to meet the objectwes established in the problem definition stage Prototypes can be produced, for increased visualization, and possibly shown to potential clients or focus groups in order to obtain impartant feedback.

Thought must be given to Issues such as how various components will be assembled, what materials should be used to build different parts estimated production costs, and other specific details. The purpose

of this stage is to consider several alternatives and develop them to a sufficient paint that an informed decision can be made,

INTRODUCTION

Gz

Firite Bement drains

DESIGN AND ANALYSIS When the field is narrwed to one Design, Parametnc computer mode are typically constructed and analyzed. The solution is revised and subjected

to

increased

scrutiny,

using

mathematics,

materials saence, technology, and simulation tools.

Flow, thermal

engineering

Forces, stresses

conductivity, and other physical properties are consid-

ered and evaluated (S68 Houre 3).

functionality, manufacturability,

[he desien |s @iamined in terms of

strength. safety, and cost

Various

standards organizations or governmental

bodies may define ewacthy

which methods must

certain aspects of the ce

sien.

CAD

minations,

software

be used to analre ts especially

crucial in assisting wath these

with certain packages being almost considered

deter-

industry

Standards

DESIGN REFINEMENT Additional testing of your designs may show weaknesses or over sights. These drawbacks may not invalidate a possible solution, but instead can be improved and optimized before the next desien iteration. Prototypes are often manutactured. and depending upon their material, could even be physically tested. Recent advances in computer aided manufacturing and additive manufacturing are popularizIng Mp Prototyping technolocees, which alloy the creation of physi cal

parts directly from

30 computer models (see Figure 4}

DESIGN IMPLEMENTATION Once the final design has been

properly Tested and analyzed, the irt-

Glemerntation step con pletes the engineering deaon protess.

At this

Stage, construction of the design begins, facilitated by a full set of engineering documents detailing the specinc steps needed to ensure

proper manufacturing, menshoned

drawings,

This documentation does nat only include dibut may

also incanparate animations,

prysica

Simulations, rendered photo-realistic images, and augmented real ity

DOCUMENTATION Documentation

is 2 complementary

of the engineering design

process.

step performed

al every

stage

It involves recording and report-

ng the functionality and details of a desien.

Technical manuals, user

guides, handbooks, instruction booklets, test results, presentation Materials, Charts, Graphs, Tachinical reports, and packing and shipping

nstructions are examples of documents developed throwghout the

product life cycle

INTRODUCTION

Si ccna allele, 1a (em mola) alare

ee (a

GERD

este Utting Devices" by Leonard Oa vinci (between 140 anc wz)

Introduction 45 an engineer, you wall need to produce, revise, and interpret drawings and models of designs, structures, and systems, Graphic com-

munication is, and has been forcenturies (see Figure 1.), the universal language that allows you to express and share technical ideas, and a

tool capable of storing @ great amount of information in a very small

space, After all, “a picture is worth a thousand words.” The connection between engineering and @raphic communication |s undeniable. The ability to visualize objects three dimensionally and

ia

“Cmossnow. by Leonaecs [eerie al rec tanll2

Da Vinci

create good quality graphics is a necessity for today's designers, architects, engineers, and anyone working in technical fields. Graphic communication facilitates the design process by helping ideas take

shape on paper, inthis chapter, we introduce the traditional method of design: sketch-

ing. We present sketching not only as an illustration toal, but alsa.as an essential part of the design methodology. Despite the computer graphics tools available today. the ability to sketch ideas quickly on paper is the only practical way to evaluate them and see which ones

are worth exploring further. You will learn about the importance of freehand sketching, particularlyin the early stages of the design process, and familiarize yourself with the most common drawing tech-

niques and practices. Lettering is discussed as an instrument to prowide textual information to drawings.

Firenand Sethe 23:feeani to commuicabe ches Ga

Sketching A sketch isa rough eraphic representation of an idea or concept (see Figure 1.2). They are quick, black and white drawings that communi-

cate the shape and size of an object without excessive attention to accuracy or details. Sketches are typically created freehand. without

the aid of drawing instruments. Sketches are used ina variety of situations: « Asa thinking process, to quickhy communicate ideas and visual(28 COnGEpTtS

To brainstorm and explore design

altartiatives cre

atively. * To record information in the field.

7 AS reminders to halp engineers reconstruct ideas and details they may otherwise forget. * Asa starting point for refined models and final designs.

Frechuid) Soetchied 26 rear 10 COMTI ate ies

Unlike artistic sketches, which are primarily focused on color, composition, texture, and aesthetics. technical sketches communicate practical details and ideas, and they are constantly subpect to changes and revisions.

Engineering sketches are generally presented ina 20 format, although pictorial drawings that show a 30 view of the object are often used for clarity. In future chapters, you will study the different projection

dL

aa

Aa Saree

FVi-4 Le a

CiPteeert uses of eietr hing

methods used in engineering drawing,

Sketching wall certainly help

you improve your visualization skills, which will have an immediate

effect om the quality of your drawings. Sketches must be clear, concise, and dark enough to stand out fram the page so they can be faxed and scanned properly. In sore cases, shading or hatching elements may be included to emphasize volumes

and shapes orto mimic the appearance and textures of some materias. Textual annotations are also common as they provide additional information to a sketch, such as dimensions, assembly instructions,

or manufacturing details. it is important that you sign and date your sketches to verity own-

ership. Use copies of your sketches for distribution and keep the originals in your archives. Sketches are considered historical and legal documents and can be presented 25 evidence in cases of lawsuits that

are brought before court Although many people do not fee! confident about their own drawing abilities, engineering sketching is a technical skill, which means that it

can be acquired and improved with practice and dedication. Common eeouses such as “lam not an artist” orl have mo artistic eye” have

ho Place in this type of sketching. In fact, many situations will onky require the use of basic sha pes. anouvs, and stick Figures to. communi cate your ideas to. others, Doodling is also good practice for sketchine Some sketching examples are shown in Fieure 1.3 CHAPTER

01

i

a

a

“a Yr

— -

7

i

a Ee

#

WRG

=

:

oh out

4

7

—

DIAGRAM

Different uses of sketchy

SKETCHING

AND

LETTERING

:

beara,

H

e

WATER

eh)

-TAwK

—

_

GRE]

Engreeingrape =

GE)

rapes

Sketching Tools There is a witke varietyof tools available for sketching,

However, since

sketches may be needed quickly. only pencil, paper, and eraser are essential,

Rulers, T-squares, tramgles,

templates, and other technical

instruments can onky slow you down during the eaty stages of a design and restrict the type of forms and shapes explored. In addition, there are many situations where these tools are not available. such as

when sketches ate created in the field or during lunch meetings, Consequently, itis important for a designer to be able to sketch without any Supporting tools. You can master this craft with adequate practice. Paper is the primary medium vehere you wall create your sketches, but you may also find yourself sketching on dry-erase boards, srmart-

phones, chalkboards, etc. There is a wide varlaty of paper choices in the market. Although good quality paper is preferred, the selection

nomally depends on availability, If you are at home or at the office you will likelyuse plainor engineering paper (see Figure .4)orasketch pad. Grid paper is also useful If you need guidance with allanment and

propartions (See Figure 7.5). lf nothing else is on hand, improvise and use what you have.

Paper napkins or the back of an envelope are

Some examples you probably have heard before,

Amy type of paper is

acceptable for quickly sketching your idegs.

Find a pencil that suits your ste and particular uses. Both mechanical and wooden pencils work well for sketching.

Lead thickness for

mechanical pencils ranges from .2 min to .gmm, with .5 and 7 mm CHAPTER

01

SH

8H

TH GH

SH 4H

3H

2H

H

(Mardiest

F

HE

B 26

Lead grades for pent

5B 6B

TB

Gan

Most wooden pencils are graded on a system that uses a stale from “H” (for handness) to “B" (for blackness), as well a5 “F", an arbitrary

letter that indicates the midpaint of the range (see Figure 16), Medium grades (HB and F) are best for sketching. Harder leads (GH - 3H) have some uses in engineering drawings, but the lines tend to be too fight, Soft leads (28 - 9B) are mostly used by artists Inthe United States there is.an alternative system to designate pencil grades that uses numbers from 1 to 4 (you are probably familiar with the popular #2 pencil), The equivalence with the previous scale is 1.7

If YOU are using a wooden pencil, keep it sharpened and hold it at an

angle of about 60 degrees to the paper. Rotate the pencil Frequently a5 you sketch to keep the wear of the lead even. Chisel shaped leads can create furzy lines with unexpected thicknesses.

Erasing lines with the purpose of making changes to a desien is not reconmimended. Erasers should be used almost eslusively to correct inaccuracies or mistakes

in lines,

In general,

soft

virnd

or qum-like

erasers are preferred as they leave loss residue when used and they

ae less likely to damage the surface of the paper.

SKETCHING

AND

8B aa

being the most popular, Leads over ¢ mm thick are not suitable for sketching

shown in Figure

38 46

Medum

LETTERING

Us

as

=i

#2%

#2

=i

Word

ZH

H

F

HB

a

Albennative scale of lead grades for perc

Fae

+

+

1, Marit endpoints

2. Place the pencil on ihe frat

4, Dirge thee ling faeet In ame angie Broke —_—_—_— | Fac.

|

DiPReeert used of sinetcheny

Sketching Techniques STRAIGHT LINES Lines are the most basic elements of sketching. They represent the

edees of objects, Lines used in sketching should be dark, consistent, and have auniform thickness. Construction lines canbe used as references and Quidelines to help you during the sketching process. They are significantly lighter in thickness, and they are generally erased when the sketch [s finalized.

A goad method to sketch straight lines freehand is to keep your eyes Fined on the endpoint of your line and draw the line inane fast stroke

(See Figure 12). Do not stare and follow the tip of the pencil while you drav the line. To prepare for the gesture. you can initially move your pencil between the two endpoints a few times without dravine, For a Particularly long line you can use a combination of shorter strokes,

breaking the land line inte shorter segments. Do not be afraid te ro-

tate the paperas you sketch to find your most efficient angle You can practice by creating two points on a paper and trying te conect them with one straight line. Place the two points close together first and eradually move them farther apart as you feel more comfartable sketching, Practice sketching lines at different angles too

CHAPTER

01

‘

f

¥

4. By eye mark radius on diagonals

*

= 5. Trace quadrants Ser h ire crt

i)

|

CIRCLES, ELLIPSES, AND CURVES

a

Sketching circles and ellipses is considerably more challenging than

straight lines.

The most common method uses squares and rect-

angles a5 construction elements that enclose the oncles and ellipses

The midpoints of the sides of the enclosing rectangle will be the four paints of connection with the circle or ellipse. The diagonals of the Square or rectangle wall give you the center point of the circle or ellipse Newt, by eye, mark the radius of the circle on the diagonals to get additional points on the circumference, The sketching process is shown

in Figure 7.4. Construction boxes can also be used to sketch arcs and curves.

By

combining multiple bowes together, data points on the curve can be obtained. See Figure 7.10 for some examples.

SKETCHING AND LETTERING

Shetchingcuwes

ERA

GEREN biscotti:

COMPLEX OBJECTS Virtua lly any object can be broken down inte basic elements. Straight

lines can be combined into rectangles and triangles. Circles can be

GRE

tuiting crores

used to create arcs and curves. These shapes constitute the basic building blocks of the objects you see every day. Basic shapes combine to form mare elaborate drawings. With practiog, you will be able to visualize and break objects down into their individual blocks, which will help you during the sketching process (see Figure 1.11}

Basic shapes are also the foundation for human characters (see Foure 102). Quick sketches of people can help communicate proportions and

relative sizes in your drawings. In addition, the human figure is an essential aspect in most designs in terms of usability and performance,

GERRY

stetthingpeogie

CHAPTER 01

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Although sketches are not usually drawn te scale, it is important that they are proportional.

If proportions are not correct, your sketch will

never look realistic, regardless of the quality of the lines or the level of detail you put init.

Proportion refers to the relationships between elements of a sketch As a designer, concentrate on the relative sizes and shapes of all the

elements of the sketch with respect to the whole, a well as ayrninetries, patients, and other visual indicators. A simple way to maintain proportions in your drawings is by using the overall dimensions of the object you want to sketch. Start by sketching a bounding bow defined by these dimensions. Next. create the remaining features, estimating their sizes and locations with respect to

this bounding box. Ainexample of this method is shown in Fireure 1.13 Oftentimes, the pencil can be used as @ measuring tool. In this case.

the different features of the object that is being sketched are visually compared to the length of the pencil. This information|s thenused to

estimate and judge proportions.

dL

ABCDEFGHIJKLM NOPQRSTUVWXYZ 0123456789 ABCDEFGHIJKLM NOPQRSTUVWXYZ 0123456789 ah

Single Stroke

Gothic

Letting

Vertical

{tog

and incimed dota

LETTERING Dimensions. of textual

notes, labels, remarics, and technical specifications are bits information

used to supplement

drayings.

Text is always

Necessary. as not all information can be communicated graphically. Lettering refers to fonming betters and numbers to accompany draveings. There ane many lettering stvies used for different purposes. “Old

fashioned” and artistic styles like Classic German and Old-English (see Figure 1.14),

for example,

are used in old manuscripts

that are artistic in matune such as diplomas and

and documents

certitcates

This is Old English Lettering

this is Classic German Gettering a

Somme letlering shyke: are not agorogrlatefor engieering deaeang:

Engineering drawines require a clear and unambiguous type of lettering

to ensure

adopted

feadability.

For

this reason,

many

industres

haye

ther own Ettering quadelines that are typically bated

national and international standards.

The lettering stwe shown

on in

Figure 1.15 6& known a SingleStroke Gothic and is.almost universally

SCLEpted in engineering Crawi nes

Peg

CORRECT SPACING INCORRECT SPACING

Single Stroke

Lothec

lettering

ALO TeCE seater Makes beet Unbalanced

am

16 SIMpe,

letter

easily read,

and

any

tan be made with a series of single strokes. There are no flourishes or double lines, Letters can be vertical or inclined (italic) and, with very Tew GxXCeptiONns, Onhy Capital letters are used. All letters have the same height, typically 3 mm (7/8 of an inch), al though height may vary among

different industries.

If fractions are

needed, they take up twice the height of standard letters Spacing between letters in a Cause Some letters ane wider betters needs to be adjusted This adjustment is known a5

word must be consistent, However, bethan others. the spacing between some to avoid making the text unbalanced “keming.”

Spacing between words in a sentence must be approximately equal to the width ofa fullletter, such a5 “O° or “H", Spacing between lines of text is normally half the standard lettering height, See Fleure 1.16 for an exarnpla. infinal engineering drawines, letteringis done exclusively by software Most parameters such a4 font. spacing. and better height ane mar aged automatically by the computer. During the sketching process,

it is not unusual to see annotations spread over a drawing as ideas flow and concepts take shape. In fact, this practice is encouraged a5 itis usually necessary to explain or clarify certain parts of the sketch

in these cases, proper engineering lettering should be done by hard.

SKETCHING

AND

LETTERING

Exercises SeGTCA

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that

to your school Don't

provides GimeCTiONs Thom forget to

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label the streets and the most

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Cre@ate a sketch of your house or apartment. Include 3 floor plan with the layout of the furniture. Include basic dimensions for walls CHAPTER 01

SKETCHING AND

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CHAPTER 01

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Ortnograpnic Projection

Ga

Prince! projec bon planes

Introduction A common dilemma in engineering graphics presents itself when attempting to portray three-dimensional objects in two-dimensional

space [a piece of paper), Unlike artistic drawings, which are primariy concerned with creating visually appealing representations of an

object, technical drawings require methodsbo precisely specify its geometry, size, and structure to ensure that an object is manufactured exactly as the designer intended it. The most fundamental technique invalved is called graphical projection.

Graphical projection is a system by which a three dimensional abject is represented on a planar surface, There are different graphical projection methods that are used iin technical graphics: orthographics, ObIIQUES, EODROMetrics. and Perspectives.

While ObIQUaS, Derspet-

tives, and aonometrics attempt to represent multiple faces of an object in a single drawing, orthographic projection uses a series of tyvo-

dimensional views, arranged in a standard manner,

in order to fully

document the objact’s geometry. This chapter Introduces the primary

method used in engineering: orthographic projection. The remaining techniques will be discussed in detail in subsequent chapters

Pe

ers

racket

opie

ass Geom

Fic, 2.2)

Orthographic Projection Orthographic projection is a eraphic representation method based on the creation of a group of two-dimensional views using three mutually perpendicular planes called frontal, horizontal, and profile. These

, ,

planes intersect each other at 90° angles (see Figure 2.1). To understand how orthographic projection works, visualize an object displayed inside an imaginary cube or glass box, like the bracket

shown In Figure 2.2. The edges

Oe

fi

“tena, "Nang

Ayetenonitegespane

GIR

Views projected ontethe fares of the box

[ERE]

of the bracket are projected normally onto the planes of

this imaginary glass box. ‘You can think of this concept as an observer located outside the box looking at the object inside (see Figure 2.3) The process is then repeated for the six faces of the glass bow, as shown in

Figure 2.4

ORTHOGRAPHIC PROJECTION

| Fc 2.5 |

Lirtholici ng ihe Go

to

The six faces of the box are then unfolded in a standard manner 50

BACK

LEFT

FROeT

FHT

Each orthographic view shows only two dimensions of the abjact,

orton Complete arthegaphic of tree Erect

that the top view is shown directly above the front and the side view is placed directly to the side of the front view (see Foure 2.5). The six views generated are called the principal views and they constitute the complete orthographic representation of the object (see Figure 2.6).

which means that mor than one wiew is necessary to fully describe

eqperertation

the object. For this reason, orthographic drawings are also called mulCiv

Cravens,

Orihographic views must be aligned and sufficiently spaced to allow for dimensions. Each view shares at least one dimension (width height, and depth) with another view (see Figure 27). ao

o

hack views correspond to the Frontal plane. the top and bottom views

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correspond to the profile plane. While the views associated with each plane are similar in appearance, they are mirror images of each other

aL HEWGHT

The front and

CHAPTER 02

2;

a

&

© Complete arthoy rapt

epee eriteior

of the bracieet in First Amgie Projection

Projection Methods There are hen major methods inwhich an object's views are projected onto the enclosing etass box. Inthe United States. Third Angie Projecton [5 used. which can be understood a5 view ng the object from out:

side the glass box. The examples shown in previous figures use Third Angle Projection. Imothercountries, however, the preferred method is

First Angle Projection, inwhich the viewer is looking at the object from

Tseverlocated insiders box GERRY

inside the box and the images are projected ante the planes behind

the object (see Figure 2.4 and Figure 2.9). The complete orthographic representation of the bracket in First Angle Projection is shown in Figure 2.10 Both First and Third Angle Projection methods ane valid as they re-

suit in the same six views, The difference is the arrangement of these WEN around the glass box. To avoid confusion, the type of projection must be clearly indicated with a symbol on the drawing, The projection symbol for both projection methods consists on a truncated cone

(see Figure 2.17), Third Angle Projection |s the default projection system used in the United States acconding to the standard ASME ¥14.3-2003, which regulates multiview drawings. For this reason, all the examples and

Fest Angie Peogerction

exercises in this book willuse Third Anete Projection

Op ee

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Lett: ist Angie Projection symbol Paght: 3d Angie Projection symbol

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A-A Hatch differertcomponents atiditfterent angles.

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SECTION A-A

Gaz

Full section

Typesof — Sectional Views Depending on the type of cut and how the cutting plane is manipulated, different

types of sectional views

can be generated.

Some

are more specific than others, but it is important for engineers to understand the different uses and applications of sectioned orthoGraphic views

FULL SECTIONS Full sections are created when the cutting plame passes entirely throveh the object. sltcine it in two pieces. Depending on the shape of the object. the cutting plane may pass exactly through the middle

making two identical halves, or it may be offset from the middle to cut through specific features of the object See Figure 4.12 and Figure 4.73 for an example of a full section

Fs

03 |

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A

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Offset section The pictorial draenei shown fer iliisb aban purpeces ony Go)

Visible lanes

A

must be oenitted

\\

InDor ec! Gaclonal view wilh veeible lines

Cored! seclonal ew

wilh waible lines removed

Remone visiblelines representing bends inthe cutting plane (LER

OFFSET SECTIONS An offset section is a modified version of a full section, typically used for objects with features that are not aligned and specific features that would be missed

by the continuous section created by a flat

plane (see Figure 4.14). In this type of section, the cutting plane line is manipulated and bent at qo° to make a more efficient cut that passes through the important details of the object. See Figure 4.14 and Figure 4.15 Although the edges where the cutting plane is bent theoretically should be represented with visible lines in the sectional view, they are conventionally omitted to keep the drawing clear and simple (see

Figure 4.16)

ALF ORES

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HALF SECTIONS Half sections are typically used with cylindrical and symmetric objects They are created by bending the cutting plane at 290° angle so that a quarter of the abjectis removed. The viewing direction is always parallel to one part of the cutting plane and perpendicular to the other.

The following conventions are used when working with halt sections: “O48 center line is wsed to divide the sectioned half of the abject trom the unsectioned halt * The cutting plane line 16 shown

with only one anroyvhead

and la-

beled with one letter. The sectional view Is identified with the Sanne

letter,

* All hidden lines are omitted, including those in the unsectioned half of the object

SECTION A

The drawing shown in Figure 4.78 illustrates a half section,

rial lustrations are provided for clarification purpases. GE)

(Creation of half sections:

CHAPTER 04

The picto

Creation of eveived ardvemourdsection.

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REVOLVED AND REMOVED SECTIONS Revolved and Removed sectional views result from a cut that takes avery thin slice of an object and rotates it 90° around the center axis toward the plane of projection (see Figure 4.19). These types of sec-

tional views are used to provide contour (cross-section) and material information of objects without the complexity of adding additional orthographic views.

The process of creating revolved and removed sections is iMentical The difference between the two ls that revolved sections are drawn

Revo

SSCHOn SupeTMpceed cris wer

| Fai. 2.22]

superimposed over an existing orthographic view (see Figure 4,20), whereas removed sections are offset a certain distance from the view

(se@ Figure 4.2). In revolved sections, a center line is shown to indi Cate the aos of revolution.

Revolved sections are sometimes represented between break lines to give the view focus and make it stand out from the drawing (see Figure 4.22 and Figure 4.23),

a

ok

Resolved section between treakllines EER)

Broken-Out Sections

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2007 Saturn Vue Greenline withesposed hyird components at the Washington Auto Show [pudlic domain)

BROKEN-OUT SECTIONS Broken-out sections are created by taking a small portion away fram

an object to reveal part of its intemal detail. In this type of sectional wew, the broken-out portion is part of the original view, Also, the cutting plane line is replaced by an ittegular line that is typically sketched

freehand.

This break line separates the exposed part of the abject

from the unexposed.

Unilke the other types of sections, broken-out

wews retain their hidden lines, if any,

of broken-out sections.

acne

See Figure 4 24 for amexample

ome A fF y tet

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Full section: cuiiing through ribs

Sectioning ris GERD)

Cece wath rite (top) ame full [ec

4.2

wentional wew (betinml

General and Conventional

Sectioning Practices UNHATCHED FEATURES

-

There are certain design features that are normally left unhatched

¢

when the cutting plane cuts through them in amy type of sectional

‘

P

ie Sh

wew, This practice § used to avoid misinterpretations of a drawing fue to false impressions of material thicknesses. The most common features include:

ww

* Ribs and webs: thin featunes added to objects for structural sup-

port. See Figure 4.26 to Figure 4.29.

Patton ial ews of Otject wainty evete,

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protrusions

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added

jects. See Figure 4.30

CHAPTER 04

Longitudinal section, Lug not hatched

to

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Rioctniaviewsofwtec! with fourspakes IER

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SECTION AqA SECTION A-A Incorrect (spokes hacked) «=| Correct fepokes not tether} Sec ormng spokes

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* Spokes: rods radiating from the center to the rim of awheel, See Figure 4.31 and Figure 4.32.

a

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SECTION A-A

ize)

Agseenibly section wath parts not Psstrhedd

Additionally. there are certain components that are usually not hatched when an entire assembly is sectioned, These components include fas-

heners, gaskets, rings. gears, springs, bearings, axles, and shafts

=

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CHAPTER 04

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Notice the ffects of foreshortening en the angled eurface, missing hole infoeraatinn on the right lig, and Consuming FE CP paar Fh aching ore!

lines,

Aligned section The angled features adjusted so compirte

inferrramen can be presided ina mone descr igtive Sect

weer

Aaaned 5 echo

GezzED

CONVENTIONAL ROTATIONS Conventional rotations are violations of the general rules of orthoBraphic projection, inorder to simplifyadrawing and provide increased clarity of the object. The conventional practices studied in the ortho-

graphic projection chapter also apply to sectional views, Cylindrical objects with equally spaced features but unclear ortho@raphic views, such as the one shoyyn in Figure 4.34, are typically adjusted by changing the angle between the featunes to present a view that Can be more easily understood. Objects with angled features,

such as the lug shown in Figure 4.45.

also produce orthographic views that are confusing.

Although the

cutting plane must be bent to pass through the angled features, the

effects of foreshortening and the nature of the cut do not provide a clear picture of the geometry of the object To solve this problem, the angled feature is aligned to a vertical or horizontal position, providing complete information about the object

(see Figure 4.36).

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ok

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|

Break lines

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rte ves

Broken Views and Conventional Breaks Broken views are used to Illustrate objects with uniform elongated features in such a manner that the object can be drawn at a larger scale on the paper and the features can be seen and dimensioned

more easily.

The example shown in Figure 4.97 illustrates a tiki torch

drawn at asmall scale so it can be accommodated on the paper. The

details at the end of the torch are hard to see (and ane of most interest) because of the scale used. In addition, there is inadequate space for proper dimensioning.

CHAPTER

04

=i

22 wooo

PIPE OF TUBULAR

METAL BAR

PIPE OF TUBULAR

METAL

BAR

SOUID ROD Comvemtinnial b reales

Fac. 4.30]

Since the long portion of the object is fairly uniform and contains no

essential information, it can be shortened, which allows the use of a larger scale (see Figure 4.39). Although the portionbetween the break

lines is removed from the drawing, the full-length dimension needs to be provided, just as if the entire torch was drawn. Notice the break

fine added to the dimension line te indicate the overall dimension, Different symbols can be used to represent break lines. Zig-zags. curves, and straight lines are conniman, although some conventional symbols can provide additional material information. breaks are shown in Fieure 4.99

a

Standard

ok

SECTIONAL VIEWS

Name:

CHAPTER 04

EXERCISE 01

—

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4

SKETCH THE APPROPRIATE SECTIONAL VIEW, OBJECT IS MADE OF CAST ROM.

DATE:

SECTIONAL VIEWS

Name:

CHAPTER 04

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EXERCISEO2

SKETCH THE APPROPRIATE SECTIONAL VIEW.

OBJECT IS MADE OF STEEL,

SECTIONAL

CHAPTER

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Name:

04

EXERCISE 03

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SKETCH A HALF SECTIONAL VIEW. OpecT 1 MADE OF ALUMINILIB

pelt)6 aee

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Date

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OBJECT IS MADE OF BRASS,

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SKETCH THE APPROPRIATE SECTIONAL VIEW.

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EXERCISE 07 ~~ Date

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Name

CHAPTER 04

EXERCISE 08

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SKETCH THE APPROPRIATE SECTIONAL VIEW.

OBJECT IS MADE OF RUBBER

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SECTIONAL VIEWS

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SKETCH THE APPROPRIATE SECTIONAL VIEW, OBJECT IS MADE OF BRONTE.

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CHAPTER 04

EXERCISE 11

SKETCH THE APPROPRIATE SECTIONAL VIEW. OBJECT IS MADE OF PLASTIC.

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Auxiliary Views

| ac.

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Inclireed gurtace

Introduction Certain objects cannot be accurately described with the primary principal orthographic views. In the previous chapter, you studied the use

of sectional views to represent objects with significant internal detail In this chapter, you will learn the bechniques used to properly describe objects with surfaces that are not parallel to the standard planes of projection As the geometrical complexity of parts and components increases,

sloping faces may occurs When using faces because the In the abject shown

become common features, However, distortion standard orthographic vews to represent these sloping surface is not parallel to the line of sight in Figure 5.1, the inclined surface (in gray) appears

distorted (shorter than actual size) in the top and side views and as edge 4B (true length) in the front view, making the surface difficult to wisualize In orthographic projection, visual distortion is caused by foreshorten-

ing effects (discussed in previous chapters).

Lines. angles, and fea-

tures never appear true shape and size in any standard orthographic

wew if they are located on slanted or inclined surfaces. This problem affects the perception of the object. To correct the effects of distor-

tion, and provide a more realistic representation, additional ortho-

graphic views are required. These additional views are created by prajecting the inclined surfaces of the object onto aundliary planes

CHAPTER

05

ObECtinsite glass box with additions! [PREY Alan for aud bary ware

Fanes projected onto the (Ez) planeseo? The ste

Auxiliary Views and Planes

CS

An auniliary View (5 projected onto a plane other than the three stan-

dard planes of projection (horizontal, frontal, and profile). Auxiliary planes Can be visualized a5 additional planes on the imaginary “glass box" model used in previous chapters to illustrate the creation of the

principal orthographic views. These extra planes are created parallel to the inclined surfaces (se@ Ficure 5.2) so that the true shape and

size of the surface can be depicted

Unfolding the feewith audisey plane RE

Similarly to the process followed to create the standard orthographic

Wews, the sloping faces of the object are projected perpendicularly

onto extra planes parallel to the surtaces of the “modified” glass bax (see Figure 5.3).

The faces of the box are then unfolded to create the orthographic Wiens (see Ficure 5.4) The edges or joints between the faces of the Glass bow act as “hinges” (typically referred to a5 folding lines), The planes of the modified box are presented using the same scheme

employed for the standard box,

The auxiliary view is unfolded using

the line between the auxiliary plane and the standard plane where the inclined surface appears as anedge (the front Wews, in the example). The resulting dravineg with the auxiliary wew i5 shown in Figure 5.5

pea

7

Oth nar ap

Wee

wilh alias

view

es

wo

1s 70

|b Ga

Full aucbiary view

General Practices For

Auxiliary Views

Hf all surfaces of the object are projected onto the auxiliary plane, the Wew generated is refemed to asa full aundliary view (see Figure 5.6), If only the inclined surface is projected, the view |s called a partial aunillary VIEW. Partial auxiliary Views are more commen than Full auneiliary views. Ina full auxiliary view, all surfaces other than the inclined one will appear distorted, providing little value to the drawing, if any, and may Create confusion in the viewer Hidden lines are normally omitted in ausdliary views unless required

for clarity,

Additionally, the capital letters “T.5", indicating that the

Beametry in the view is shown “True Size,” must be included in the auniliary view

CHAPTER 05

i=I © aun iiary ww

Auxiliary depends For this auxiliary wew

proected

from the tog view

Ga

views can be constructed trom any view in a drayving, but it on the wew where the inclined surface appears as an edge reason, some authors will refer to aundiliary views as front ew, top auxiliary view, or side auxiliary view, based on the

from

which

they originate.

Other authors

use the terms

depth

auxiliary view (if projected from the front view), height aundliary view (if projected from the top view), and width auxiliary wew (if projected from the site view), to identify the dimension that is shown tre s/270 Auxiliary views can also be constructed from other auniliary views An auviliary view that is projected fromm one of the principal views is referred to as primary auxiliary wew. From a primary auxiliary view, @ Se0ondary auxiliary view can be projected; then fram it, a thind aux-

Hiary view, and soon,

Although an unlimited number of successive

auxiliary Wews can be created, most objects can be adequately desorbed with primary or secondary auxiliary views. See Figure 5.7 for an example of auxiliary view projected fram the top view

pea

7

SS

“i

—_

Gaz

Humber

comers ef the incined

curface ina wey

nese it appearsasa surface not an edge

Construction of

Auxiliary Views While most

parametric

CAD

packages

will easily create auxiliary

views, the following steps Illustrate the method used to create them by hand. Label the conners of the inclined surface in an orthographic Wew where the inclined surface appears asa face, not asanedge, Al though you may be able to easily identify the comers meritally, it Is good practice to label them. In the example shown in Figure 5.44, the top view is used to create the auxiliary view, although the right side view is also acceptable since the inclined surface also appears as aface in this wew

CHAPTER 05

2

&

1,2