1. Study Lesson 1
Introduction

2. Contents Engineering drawing Drawing standards Drawing sheet Scale
Lettering
Line types

3. Engineering Drawing --Albert Einstein
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

4. Effectiveness of Graphic Language
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.
You can easily understand that …
The word language is inadequate for describing the size, shape and features completely as well as concisely.

5. 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

6. Ways to Create an Engineering Drawing
A drawing can be created in 3 ways
Freehand sketch
Using typical drawing instruments
Using a computer

7. Create a Drawing : Freehand sketch
The lines are drawn using only pencil and erasers on a blank or grid paper.
Example
Pictorial sketch
Orthographic sketch

8. 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

9. Create a Drawing : Using a computer
Computer aided drafting (CAD) software is used.
Example
2D drawing
Solid modeling

10. 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.

11. Text on drawings : Example
Dimensions
&
Notes
General
notes
Title
block

12. Knowledge and Skills Require
Engineering Drawing
Graphics
language
Word
language
Using line types
Geometric
construction
Visualization
Projection
method
Dimensions & Notes
Visualization is the ability to mentally picture things that do not exists.
Contents

13. Drawing Standard
Drawing sheet
Scale
Lettering
Line types
Contents

14. 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.

15. Standard Code Country Code Full name ANSI
American National Standard Institute
USA
JIS
Japanese Industrial Standard
Japan BS
British Standard UK AS
Australian Standard
Australia
Deutsches Institut für Normung
DIN
Germany
ISO
International Standards Organization

16. Drawing Standard Drawing Sheet
Contents

17. Drawing Sheet : Standard size
Trimmed paper of
a size A0 ~ A4. A4 A3
Standard sheet size (JIS)
A x 297
A x 420
A x 594
A x 841
A x 1189 A2 A1 A0
(Dimensions in millimeters)

18. Drawing Sheet : Orientation & Margin
1. Type X (A0~A4) c
Sheet size c (min) d (min) A A A A A d c
Border
lines
Drawing space c
Title block
2. Type Y (A4 only) d
Drawing
space
Title block

19. Drawing Standard Drawing Scale
Contents

20. Drawing Scales : Definition
Length, size
Scale is a ratio between the linear dimension of a drawn representation of an object and the actual object. : 1 2
Drawing
Actual

21. Drawing Scales : Designation
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 scale is commonly found in a title block.

22. Drawing Scales : Notes
Dimension numbers shown in the drawing represent
the “true size” of an object and they are independent of
the drawing scale used.

23. Drawing Scales : Standard scale
Standard reducing scales are
1:2, 1:5, 1:10, 1:20, 1:50, 1:100
Standard enlarging scales are
2:1, 5:1, 10:1, 20:1, 50:1, 100:1

24. Drawing Standard Lettering
Contents

25. Recommendation Text’s style on the drawing Examples
must have the following
2 properties
Examples
GOOD
Not uniform in style.
Legibility
- Shape
Space between letters
Space between words
Not uniform in height.
Not uniformly vertical.
Uniformity
Not uniform in
thickness of stroke.
- Size (or text height) - line thickness
Inappropriate space
between letters

26. 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.

27. Basic Strokes Straight Slanted Horizontal Curved Examples “I” letter
“A” letter
“B” letter 4 5 1 1 1 2 6 3 3 2

28. Suggested Strokes Sequence
Upper-case Letters & Numerals
Straight line
letters
Curved line
letters
&
Numerals

29. Lower-case Letters

30. Stroke Sequence : Upper-caseI L T F E H
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31. Stroke Sequence : Upper-caseV X W
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32. Stroke Sequence : Upper-caseM K Z Y A 4
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33. Stroke Sequence : Upper-caseG
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34. Stroke Sequence : Upper-caseD U P B R J
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35. Stroke Sequence : Upper-case1 2 5 7
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36. Stroke Sequence : Upper-case3 6 8 9
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37. Stroke Sequence : Lower-casei
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38. Stroke Sequence : Lower-casev w x k z
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39. Stroke Sequence : Lower-casej y f t r
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40. Stroke Sequence : Lower-caseb d p q e
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41. Stroke Sequence : Lower-caseg n m h u s
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42. DRAWING D R A W I N G Word Composition
Space between the letters depends on the adjacent
contour of the letters.
DRAWING
Non-uniform
spacing D R A W I N G
Uniform
spacing
Word having non-uniform spacing is more readable.

43. DRAWING Word Composition
Contour
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

44. Sentence Composition ALL O DIMENSIONS O ARE O IN MILLIMETERS O UNLESS
Leave the space between words equal to the space requires for writing a letter “O”.
Example
ALL O
DIMENSIONS O
ARE O IN
MILLIMETERS O
UNLESS
OTHERWISE O
SPECIFIED.

45. Drawing Standard Line Types
Contents

46. Name according to application
Basic Line Types &
Name according to application
Thickness
1. Dimension line
2. Extension line
3. Leader line
Thick
Thin
Visible line
Style
Continuous
Hidden line
Dash
Chain
Center line
1. Visible line
represent features that can be seen in the current view.
2. Dimension line
Extension line
Leader line
indicate the sizes and location of features.
3. Hidden line
represent features that can not be seen in the current view.
4. Center line
represents symmetry, path of motion, centers of circles,
axis of axisymmetrical parts

47. Example
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