Chapter 1
Introduction
Contents
Drawing standards
Engineering drawing
Drawing sheet
Scale
Lettering
Line types
Engineering
Drawing
The words of the language, as they are written or spoken, do not seem to play any role in my
mechanism of thought. The psychical entities which seem to serve as elements in thought are
certain signs and more or less clear images which can be “voluntarily” reproduced and
combined--this combinatory play seems to be the essential feature in productive thought before
there is any connection with logical construction in words or other kinds of signs which are
communicated to others
--Albert Einstein
Contents
1. Try to write a description of
this object.
2. Test your written description
by having someone attempt
to make a sketch or visualize
from your description.
Effectiveness of Graphic Language
The word language is inadequate for describing the size,
shape and features completely as well as concisely.
You can easily understand that …
Graphic Language in
Engineering Drawing
“Engineering drawing” or “blueprint” uses lines to
represent the features of an object.
Features of an object are surface (include plane) and
edge.
Surface
Edge
A drawing can be created in 3 ways
Ways to Create an
Engineering Drawing
1. Freehand sketch
2. Using typical drawing instruments
3. Using a computer
Example
Create a Drawing : Freehand sketch
The lines are drawn using only pencil and erasers on a
blank or grid paper.
Pictorial sketch Orthographic sketch
Example
Create a Drawing : Using instruments
Drawing instruments are used to
draw straight lines, circles, and
curves concisely and accurately.
Drawings are usually made to scale.
Example
Create a Drawing : Using a computer
Computer aided drafting (CAD) software is used.
2D drawing Solid modeling
Elements of a Drawing
A clear and precise engineering drawing requires both
graphics and word languages.
Graphics language
Describe a shape (mainly).
Word language
Describe an exact size,
location and specification
of the object.
Text on drawings : Example
General
notes Title
block
Dimensions
&
Notes
Knowledge and Skills Require
Graphics
language
Word
language
Dimensions & Notes
Visualization is the ability to mentally picture things that do not exists.
VisualizationUsing line types
Geometric
construction
Projection
method
Engineering Drawing
Contents
Drawing Standard
Drawing sheet Scale Lettering Line types Contents
Definition and Necessity
Drawing standards are set of rules that govern how
technical drawings are represented.
Drawing standards are used so that drawings convey
the same meaning to everyone who reads them.
ISO International Standards Organization
Standard Code
ANSI American National Standard InstituteUSA
JIS Japanese Industrial StandardJapan
BS British StandardUK
AS Australian StandardAustralia
Deutsches Institut für NormungDINGermany
Country Code Full name
มอก./TIS สำนักงำนมำตรฐำนผลิตภัณฑ์อุตสำหกรรมThailand
Examples of TIS Standard
มอก. 210 2520 วิธีเขียนแบบทั่วไป : ทำงเครื่องกล
มอก. 440 ล.1 2541 กำรเขียนแบบก่อสร้ำงเล่ม 1 ทั่วไป
มอก. 446 ล.4 2532 ข้อแนะนำสำหรับกำรเขียนแผนภำพวงจรไฟฟ้ำ
มอก. 1473 2540 กำรเขียนแบบเทคนิค กำรติดตั้ง
สัญลักษณ์สำหรับระบบท่อของเหลว
ระบบทำควำมร้อน กำรระบำยอำกำศ
และระบบท่ออำกำศ
Code number Contents
ที่มำ : http://library.tisi.go.th/data/lib_resources/pdf/catalog-online49/tis/02_ICS.pdf
JIS Z 8311 Sizes and Format of Drawings
JIS Z 8312 Line Conventions
JIS Z 8313 Lettering
JIS Z 8314 Scales
JIS Z 8315 Projection methods
JIS Z 8316 Presentation of Views and Sections
JIS Z 8317 Dimensioning
Code number Contents
Examples of JIS Standard
Drawing Standard
Drawing Sheet
Drawing standard Contents
Drawing Sheet : Standard size
Trimmed paper of
a size A0 ~ A4.
Standard sheet size
(JIS)
A4 210 x 297
A3 297 x 420
A2 420 x 594
A1 594 x 841
A0 841 x 1189
A4
A3
A2
A1
A0
(Dimensions in millimeters)
Drawing space
Drawing
space
Title block
d
d
c
c
cBorder
lines
1. Type X (A0~A4)
2. Type Y (A4 only)
Title block
Sheet size c (min) d (min)
A4 10 25
A3 10 25
A2 10 25
A1 20 25
A0 20 25
Drawing Sheet : Orientation & Margin
Drawing Standard
Drawing Scale
Drawing standard Contents
Drawing Scales : Definition
Drawing Actual
Length, size
:
Scale is a ratio between the linear dimension of a
drawn representation of an object and the actual object.
1 2
Designation of a scale consists of the word “SCALE”
followed by the indication of its ratio, as follows
SCALE 1:1 for full size
SCALE X:1 (X > 1) for an enlargement scales
SCALE 1:X (X > 1) for a reduction scales
Drawing Scales : Designation
Drawing scale is commonly found in a title block.
Dimension numbers shown in the drawing represent
the “true size” of an object and they are independent of
the drawing scale used.
Drawing Scales : Notes
Standard reducing scales are
1:2, 1:5, 1:10, 1:20, 1:50, 1:100
Drawing Scales : Standard scale
Standard enlarging scales are
2:1, 5:1, 10:1, 20:1, 50:1, 100:1
Drawing Standard
Lettering
Drawing standard Contents
- Size (or text height)
- line thickness
- Shape
- Space between letters
- Space between words
Recommendation
Legibility
Uniformity
Text’s style on the drawing
must have the following
2 properties
Examples
GOOD
Not uniform in style.
Not uniform in height.
Not uniformly vertical.
Not uniform in
thickness of stroke.
Inappropriate space
between letters
Style (this course)
Gothic vertical style.
Begin the sentence, phrase or word with a capital letter.
Text height 2~3 mm.
Space between lines of text is about of text height.
Height of the lower-case letter is about 2/3 of that of a
capital letter.
Basic Strokes
Straight Slanted CurvedHorizontal
1 1 2
3
“I” letter “A” letter
1
2
3
4 5
6
“B” letter
Examples
Suggested Strokes Sequence
Straight line
letters
Curved line
letters
&
Numerals
Upper-case Letters & Numerals
Lower-case Letters
I L T F
E H
Stroke Sequence : Upper-case
Skip section
V X W
Stroke Sequence : Upper-case
Skip section
N M K Z
Y A 4
Stroke Sequence : Upper-case
Skip section
O Q C G
Stroke Sequence : Upper-case
Skip section
D U P B
R J
Stroke Sequence : Upper-case
Skip section
5 7
Stroke Sequence : Upper-case
1 2
Skip section
6
8 9
0S 3
Stroke Sequence : Upper-case
Skip section
l i
Stroke Sequence : Lower-case
Skip section
v w x k
z
Stroke Sequence : Lower-case
Skip section
j y f
r
t
Stroke Sequence : Lower-case
Skip section
c o a b
d p q e
Stroke Sequence : Lower-case
Skip section
g n m h
u s
Stroke Sequence : Lower-case
Skip section
DRAWING
Word Composition
Non-uniform
spacing
Uniform
spacing
DR A W ING
Space between the letters depends on the adjacent
contour of the letters.
Word having non-uniform spacing is more readable.
Word Composition
Contour
DRAWING
Contour can be denoted as “straight”, “slant” and “curve”.
Adjacent contour can be
1. straight-straight : II, IN, IM, IP etc.
2. straight-curve (or curve-straight) : IO, QR etc.
3. straight-slant (or slant-straight) : IV, IW etc.
4. curve-curve : OO, OG etc.
5. slant-curve (or curve-slant) : VO, WG, VC etc.
6. slant-slant : VW, VX etc.
Spacing
Leave the space between words equal to the space
requires for writing a letter “O”.
Example
Sentence Composition
ALL DIMENSIONS ARE IN
MILLIMETERS
O O O
OUNLESS
OTHERWISE SPECIFIED.O
Drawing Standard
Line Types
Drawing standard Contents
Basic Line Types &
Name according to application
Continuous
Dash
Chain
Style
Thickness Thick Thin 1. Dimension line
2. Extension line
3. Leader line
Center line
Hidden line
Visible line
represent features that can be seen in the current view.
represent features that can not be seen in the current view.
represents symmetry, path of motion, centers of circles,
axis of axisymmetrical parts
indicate the sizes and location of features.
1. Visible line
3. Hidden line
4. Center line
2. Dimension line
Extension line
Leader line
Example
Contents

Engineering drawing chapter 01 introduction

  • 1.
  • 2.
  • 3.
    Engineering Drawing The words ofthe language, as they are written or spoken, do not seem to play any role in my mechanism of thought. The psychical entities which seem to serve as elements in thought are certain signs and more or less clear images which can be “voluntarily” reproduced and combined--this combinatory play seems to be the essential feature in productive thought before there is any connection with logical construction in words or other kinds of signs which are communicated to others --Albert Einstein Contents
  • 4.
    1. Try towrite a description of this object. 2. Test your written description by having someone attempt to make a sketch or visualize from your description. Effectiveness of Graphic Language The word language is inadequate for describing the size, shape and features completely as well as concisely. You can easily understand that …
  • 5.
    Graphic Language in EngineeringDrawing “Engineering drawing” or “blueprint” uses lines to represent the features of an object. Features of an object are surface (include plane) and edge. Surface Edge
  • 6.
    A drawing canbe created in 3 ways Ways to Create an Engineering Drawing 1. Freehand sketch 2. Using typical drawing instruments 3. Using a computer
  • 7.
    Example Create a Drawing: Freehand sketch The lines are drawn using only pencil and erasers on a blank or grid paper. Pictorial sketch Orthographic sketch
  • 8.
    Example Create a Drawing: Using instruments Drawing instruments are used to draw straight lines, circles, and curves concisely and accurately. Drawings are usually made to scale.
  • 9.
    Example Create a Drawing: Using a computer Computer aided drafting (CAD) software is used. 2D drawing Solid modeling
  • 10.
    Elements of aDrawing A clear and precise engineering drawing requires both graphics and word languages. Graphics language Describe a shape (mainly). Word language Describe an exact size, location and specification of the object.
  • 11.
    Text on drawings: Example General notes Title block Dimensions & Notes
  • 12.
    Knowledge and SkillsRequire Graphics language Word language Dimensions & Notes Visualization is the ability to mentally picture things that do not exists. VisualizationUsing line types Geometric construction Projection method Engineering Drawing Contents
  • 13.
    Drawing Standard Drawing sheetScale Lettering Line types Contents
  • 14.
    Definition and Necessity Drawingstandards are set of rules that govern how technical drawings are represented. Drawing standards are used so that drawings convey the same meaning to everyone who reads them.
  • 15.
    ISO International StandardsOrganization Standard Code ANSI American National Standard InstituteUSA JIS Japanese Industrial StandardJapan BS British StandardUK AS Australian StandardAustralia Deutsches Institut für NormungDINGermany Country Code Full name มอก./TIS สำนักงำนมำตรฐำนผลิตภัณฑ์อุตสำหกรรมThailand
  • 16.
    Examples of TISStandard มอก. 210 2520 วิธีเขียนแบบทั่วไป : ทำงเครื่องกล มอก. 440 ล.1 2541 กำรเขียนแบบก่อสร้ำงเล่ม 1 ทั่วไป มอก. 446 ล.4 2532 ข้อแนะนำสำหรับกำรเขียนแผนภำพวงจรไฟฟ้ำ มอก. 1473 2540 กำรเขียนแบบเทคนิค กำรติดตั้ง สัญลักษณ์สำหรับระบบท่อของเหลว ระบบทำควำมร้อน กำรระบำยอำกำศ และระบบท่ออำกำศ Code number Contents ที่มำ : http://library.tisi.go.th/data/lib_resources/pdf/catalog-online49/tis/02_ICS.pdf
  • 17.
    JIS Z 8311Sizes and Format of Drawings JIS Z 8312 Line Conventions JIS Z 8313 Lettering JIS Z 8314 Scales JIS Z 8315 Projection methods JIS Z 8316 Presentation of Views and Sections JIS Z 8317 Dimensioning Code number Contents Examples of JIS Standard
  • 18.
  • 19.
    Drawing Sheet :Standard size Trimmed paper of a size A0 ~ A4. Standard sheet size (JIS) A4 210 x 297 A3 297 x 420 A2 420 x 594 A1 594 x 841 A0 841 x 1189 A4 A3 A2 A1 A0 (Dimensions in millimeters)
  • 20.
    Drawing space Drawing space Title block d d c c cBorder lines 1.Type X (A0~A4) 2. Type Y (A4 only) Title block Sheet size c (min) d (min) A4 10 25 A3 10 25 A2 10 25 A1 20 25 A0 20 25 Drawing Sheet : Orientation & Margin
  • 21.
  • 22.
    Drawing Scales :Definition Drawing Actual Length, size : Scale is a ratio between the linear dimension of a drawn representation of an object and the actual object. 1 2
  • 23.
    Designation of ascale consists of the word “SCALE” followed by the indication of its ratio, as follows SCALE 1:1 for full size SCALE X:1 (X > 1) for an enlargement scales SCALE 1:X (X > 1) for a reduction scales Drawing Scales : Designation Drawing scale is commonly found in a title block.
  • 24.
    Dimension numbers shownin the drawing represent the “true size” of an object and they are independent of the drawing scale used. Drawing Scales : Notes
  • 25.
    Standard reducing scalesare 1:2, 1:5, 1:10, 1:20, 1:50, 1:100 Drawing Scales : Standard scale Standard enlarging scales are 2:1, 5:1, 10:1, 20:1, 50:1, 100:1
  • 26.
  • 27.
    - Size (ortext height) - line thickness - Shape - Space between letters - Space between words Recommendation Legibility Uniformity Text’s style on the drawing must have the following 2 properties Examples GOOD Not uniform in style. Not uniform in height. Not uniformly vertical. Not uniform in thickness of stroke. Inappropriate space between letters
  • 28.
    Style (this course) Gothicvertical style. Begin the sentence, phrase or word with a capital letter. Text height 2~3 mm. Space between lines of text is about of text height. Height of the lower-case letter is about 2/3 of that of a capital letter.
  • 29.
    Basic Strokes Straight SlantedCurvedHorizontal 1 1 2 3 “I” letter “A” letter 1 2 3 4 5 6 “B” letter Examples
  • 30.
    Suggested Strokes Sequence Straightline letters Curved line letters & Numerals Upper-case Letters & Numerals
  • 31.
  • 32.
    I L TF E H Stroke Sequence : Upper-case Skip section
  • 33.
    V X W StrokeSequence : Upper-case Skip section
  • 34.
    N M KZ Y A 4 Stroke Sequence : Upper-case Skip section
  • 35.
    O Q CG Stroke Sequence : Upper-case Skip section
  • 36.
    D U PB R J Stroke Sequence : Upper-case Skip section
  • 37.
    5 7 Stroke Sequence: Upper-case 1 2 Skip section
  • 38.
    6 8 9 0S 3 StrokeSequence : Upper-case Skip section
  • 39.
    l i Stroke Sequence: Lower-case Skip section
  • 40.
    v w xk z Stroke Sequence : Lower-case Skip section
  • 41.
    j y f r t StrokeSequence : Lower-case Skip section
  • 42.
    c o ab d p q e Stroke Sequence : Lower-case Skip section
  • 43.
    g n mh u s Stroke Sequence : Lower-case Skip section
  • 44.
    DRAWING Word Composition Non-uniform spacing Uniform spacing DR AW ING Space between the letters depends on the adjacent contour of the letters. Word having non-uniform spacing is more readable.
  • 45.
    Word Composition Contour DRAWING Contour canbe denoted as “straight”, “slant” and “curve”. Adjacent contour can be 1. straight-straight : II, IN, IM, IP etc. 2. straight-curve (or curve-straight) : IO, QR etc. 3. straight-slant (or slant-straight) : IV, IW etc. 4. curve-curve : OO, OG etc. 5. slant-curve (or curve-slant) : VO, WG, VC etc. 6. slant-slant : VW, VX etc. Spacing
  • 46.
    Leave the spacebetween words equal to the space requires for writing a letter “O”. Example Sentence Composition ALL DIMENSIONS ARE IN MILLIMETERS O O O OUNLESS OTHERWISE SPECIFIED.O
  • 47.
  • 48.
    Basic Line Types& Name according to application Continuous Dash Chain Style Thickness Thick Thin 1. Dimension line 2. Extension line 3. Leader line Center line Hidden line Visible line represent features that can be seen in the current view. represent features that can not be seen in the current view. represents symmetry, path of motion, centers of circles, axis of axisymmetrical parts indicate the sizes and location of features. 1. Visible line 3. Hidden line 4. Center line 2. Dimension line Extension line Leader line
  • 49.