Multi-View Drawing
Chapter 5
Engineering Design Technology
Sacramento City College
Multi-View Drawing
1
Objectives
 Identify
and select the various views of an
object.
 Determine the number of views needed to
describe fully the shape and size of an
object.
 Define the term orthographic projection
 Describe the difference between first and
third-angle projection.
2
Multi-View
Drawing
Objectives
 Visualize
the “glass box” concept and apply
it to the process of selecting and locating
views on a drawing.
3
Multi-View
Drawing
Objectives
 Develop a
multi-view drawing, following a
prescribed step-by-step process, from the
initial idea to a finished drawing.
4
Multi-View
Drawing
Vocabulary
 First
angle
projection
 Front View
 Horizontal Plane
 Implementation
 Multi-view
Drawing
 Negative Cylinder
 Normal Views
 Orthographic
Projection
 Pictorial Drawing
5
Multi-View
 Profile
plane
 Quadrant
 Right-side View
 Solid Model
 Spherical
 Third-angle
Projection
 Top View
 Vertical Plane
 Visualization
Drawing
Communication
 People communicate
by verbal and written
language and graphic (pictorial) means.
 Technical
drawings are a graphical means
to communicate.
 When accurate
visual understanding is
necessary, technical drawing is the most
exact method that can be used.
6
Multi-View
Drawing
Visualization and Implementation
 Technical
drawing involves:
Visualization
The
ability to see clearly in the mind’s
eye what a machine, device or object
looks like.
Implementation
The
process of drawing the object that
has been visualized.
7
Multi-View
Drawing
Visualization and Implementation
A
technical drawing, properly made, gives a
clearer, more accurate description of an
object than a photograph or written
explanation.
8
Multi-View
Drawing
Visualization and Implementation
 Technical
drawings made according to
standard rules result in views that give an
exact visual description of an object.
 The
multi-view drawing is the major type of
drawing used in the industry.
9
Multi-View
Drawing
Multi-View Drawing
A
photograph can show three views
Front.
Top.
Right Side.
 Nearly
10
all objects have six sides, not three.
Multi-View
Drawing
Multi-View Drawing
11
Multi-View
Drawing
Multi-View Drawing
 If
an object could be shown in a single
photograph, it would also include
A left-side view.
A rear view.
A bottom view.
12
Multi-View
Drawing
Pictorial Drawing
 An
object cannot be photographed if it has
not been built (!)
 This
limits the usefulness of photographs to
“show what an object looks like” (!)
13
Multi-View
Drawing
Pictorial Drawing
A
pictorial drawing
Is a drawing.
Shows an object as it would appear in
a photograph.
Shows the way an object looks, in
general.
It does not show, the exact forms and
relationships of the parts that make
up the object.
14
Multi-View
Drawing
Pictorial Drawing
A
pictorial drawing
Shows the object as it appears, not
as it really is.
Holes in the base appear as ellipses,
not as true circles.
15
Multi-View
Drawing
Pictorial Drawing
Photograph
Pictorial Drawing
16
Multi-View
Drawing
Multi-View Drawing
 The
goal, is to represent an object on a
sheet of paper in a way that described its
exact shape and proportions.
 To
do this: Draw views of the object as it is
seen from different positions.
17
Multi-View
Drawing
Multi-View Drawing
 These
views are then arranged in a
standard order.
 Anyone
familiar with drafting practices can
understand them immediately.
18
Multi-View
Drawing
Multi-View Drawing
 To
describe accurately the shape of each
view imagine a position
Directly in front of the object.
Directly above the object.
On the right side of the object.
19
Multi-View
Drawing
Multi-View Drawing
 The
front, top and right side views are the
ones most often used to describe an object
in technical drawing.
 They
20
are called the Normal views.
Multi-View
Drawing
The Relationship of Views
 Views must
be placed in proper
relationship to each other.
The Top View is directly above the
Front View
The Right-side View is directly to the
right of the Front View.
21
Multi-View
Drawing
The Relationship of Views
 When the
views are placed in proper
relationship to one another, the result is a
multi-view drawing.
 Multi-view
drawing is the exact
representation of an object on one plane.
22
Multi-View
Drawing
The Relationship of Views
 Other
views may also be required.
 The proper relationship of the six views is
shown below
Top View
Rear
View
Left-side
View
Front View Right-side
View
Bottom View
23
“Normal
views”
Multi-View
Drawing
V-Block
24
Multi-View
Drawing
Orthographic Projection
 These
views are developed through the
principles of orthographic projection
Ortho - “straight” or “at right angles”.
Graphic - “written” or “drawn”.
Projection - from two Latin words:
Pro,
meaning “forward”
Jacere, meaning “to throw”
The
literal meaning is “thrown
forward, drawn at right angles”.
25
Multi-View
Drawing
Orthographic Projection
 Definition:
Orthographic projection is:
the method of representing the exact
form of an object
in two or more views
on planes usually at right angles to
each other,
by lines drawn perpendicular from the
object to the planes.
26
Multi-View
Drawing
Orthographic Projection
 An
orthographic projection drawing is a
representation of the separate views of an
object on a two-dimensional surface.
 It
reveals the width, depth and height of an
object.
27
Multi-View
Drawing
Orthographic Projection
28
Multi-View
Drawing
Angles of Projection
Multi-View Drawing
29
Angles of Projection
 On
a technical drawing, a plane is an
imaginary flat surface that has no
thickness.
 Orthographic projection involves the use of
three planes.
Vertical plane.
Horizontal plane.
Profile plane.
 A view of an object is projected and drawn
on each plane.
30
Multi-View
Drawing
Angles of Projection
31

The vertical and
horizontal planes divide
space into four
quadrants (quarters of
a circle).

In orthographic
projection, quadrants
are usually called
angles.

Thus we get the names,
first-angle projection
and third angle
projection
Multi-View
Drawing
Angles of Projection
 First
angle projection
is used in European countries.
 Third
angle projection
is used in the US and Canada.
 Second and
fourth angle projection
is not used in any country.
32
Multi-View
Drawing
First-Angle Projection
 First-angle
projection
Front view = vertical plane.
Top view = horizontal plane.
Left side view = profile plane.
33
Multi-View
Drawing
First-Angle Projection
 In
first angle projection,
the Front View is located above the
Top View.
The Left-side View is to the right of
the Front View.
Refer
34
to Figure 5-12.
Multi-View
Drawing
First-Angle Projection
 In
first-angle projection,
the projection plane is on the far side
of the object from the viewer.
The
views of the object are projected
to the rear and onto the projection
plane instead of being projected
forward.
35
Multi-View
Drawing
First-Angle Projection
 First-angle
projection
Front
view = projected to vertical plane.
Top view = projected to horizontal plane.
Left side view = projected to profile plane.
First
36
angle
Third
Multi-View
Drawing
angle
Third-Angle Projection
 Third-angle
projection
Front
view = projected to vertical plane.
Top view = projected to horizontal plane.
Right side view = projected to profile plane.
First
37
angle
Third
Multi-View
Drawing
angle
Third-Angle Projection
 In
third-angle projection
the Top View is located above the
Front View.
The Right-Side View is to the right of
the Front View.
Refer
38
to Figure 5-14.
Multi-View
Drawing
Third-Angle Projection
 The
views appear in their natural positions.
The Top View appears above the
front view.
The Right-Side View is to the right of
the Front View.
The Left-Side View is to the left of the
front view.
39
Multi-View
Drawing
The Glass Box
Multi-View Drawing
40
The Glass Box
 In
each case, the three views have been
developed by using imaginary transparent
planes.
The views are projected onto these
planes.
41
Multi-View
Drawing
The Glass Box
 Visualize
a glass box around the object
Project
the view of the object onto a
side of the box.
“Unfold
the box” to one plane.
The
views will be in their relative
positions.
42
Multi-View
Drawing
The Glass Box
43
Multi-View
Drawing
The Glass Box
44
Multi-View
Drawing
Projection of Lines
Multi-View Drawing
45
Projection of Lines
 There
are four kinds of straight lines found
on objects in drawings
Horizontal.
Vertical.
Inclined.
Oblique.
 Each
line is projected by locating its
endpoint.
46
Multi-View
Drawing
Horizontal Lines
 Horizontal
lines
Are parallel to the frontal plane.
Are parallel to the top plane.
Are perpendicular to the profile plane.
(right-side view)
(Parallel
Appear
as true length in two
Frontal
Appear
to 2; perpendicular to 1)
and Top planes.
as a point in the third.
Right-side
47
plane
Multi-View
Drawing
Vertical Lines
 Vertical
Lines
Are parallel to the frontal plane.
Are parallel to the profile plane.
Are perpendicular to the horizontal
plane.
(Parallel
Appear
true length in two planes:
Frontal
Appear
to 2; perpendicular to 1)
and Profile planes.
as a point in the third:
Horizontal
48
plane.
Multi-View
Drawing
Inclined Lines
 Inclined
Lines
Are parallel to one plane of
projection.
Are inclined in the other two planes.
(Parallel
Appear
to only 1; shortened in 2)
true length in one of the
planes.
Appear shortened in the other two
planes.
49
Multi-View
Drawing
Oblique Lines
 Oblique
Lines
Are neither parallel nor perpendicular
to any of the planes or projections (!)
Appear
shortened in all three planes
of projection.
Can
only be drawn by locating and
connecting line endpoints.
50
Multi-View
Drawing
Curved Lines
 Curved
Lines may be
Circular.
Elliptical.
Parabolic.
Hyperbolic.
Some other geometric curve form.
 They may
51
also be irregular curves.
Multi-View
Drawing
Projection of Surfaces
 Surfaces may
be
Horizontal.
Vertical.
Inclined.
Oblique.
Curved.
 They are drawn by locating the end points
of the lines that outline their shape.
52
Multi-View
Drawing
Horizontal Surfaces
 Horizontal
surfaces
Are parallel to the horizontal
projection plane
Appear true size and shape in the
Top View.
53
Multi-View
Drawing
Vertical Surfaces
 Vertical
surfaces
Are parallel to one or the other of the
frontal or profile planes, and
Appear in their true size and shape in
the Front View or the Right-side View.
 They
are perpendicular to the other two
planes and appear as lines in these planes
54
Multi-View
Drawing
Inclined Surfaces
 Inclined
surfaces
Are neither horizontal nor vertical
Are perpendicular to one of the
projection planes and appear as a
true length line in this view.
55
Multi-View
Drawing
Oblique Surfaces
 Oblique
Surfaces
Are neither parallel nor perpendicular
to any of the planes of projection.
They
appear as a surface in all views
but not in their true size and shape.
56
Multi-View
Drawing
Curved Surfaces
Multi-View Drawing
57
Curved Surfaces
 May
be
a single curved surface (cone or
cylinder)
a double curved surface (sphere,
spheroid or torus
a warped surface
58
Multi-View
Drawing
Curved Surfaces
 Appear
as circles in one view and as
rectangles in the other view
59
Multi-View
Drawing
Techniques for Special Lines and
Surfaces
Multi-View Drawing
60
Techniques for Special Lines and Surfaces
 To
describe an object fully, show every
feature in every view, whether or not it can
ordinarily be seen
 Also
include other lines that are not part of
the object to clarify relationships and
positions in the drawing
61
Multi-View
Drawing
Techniques for Special Lines and Surfaces
 Special
line symbols are used to
differentiate between object lines and lines
that have other special meanings
62
Multi-View
Drawing
Hidden Lines
Multi-View Drawing
63
Hidden Lines
 Both
interior and exterior features are
projected in the same way.
64
Multi-View
Drawing
Hidden Lines
 Parts that
cannot be seen in the views are
drawn with hidden lines.
 Hidden
65
lines are made up of short dashes.
Multi-View
Drawing
Hidden Lines
 The
first line of a hidden line touches the
line where it starts.
Refer to Figure 5-18A.
66
Multi-View
Drawing
Hidden Lines
 If
a hidden line is a continuation of a visible
line, space is left between the visible line
and the first dash of the hidden line.
Refer to Figure 5-18B.
67
Multi-View
Drawing
Hidden Lines
 If
the hidden lines show corners, the
dashes touch the corners.
Refer to Figure 5-18C.
68
Multi-View
Drawing
Hidden Lines
 Dashes
for hidden arcs start and end at the
tangent points.
Refer to Figure 5-19A.
69
Multi-View
Drawing
Hidden Lines
 When a
hidden arc is tangent to a visible
line, leave a space.
Refer to Figure 5-19B.
70
Multi-View
Drawing
Hidden Lines
 When a
hidden line and a visible line
project at the same place, show the visible
line.
Refer to Figure 5-19C.
71
Multi-View
Drawing
Hidden Lines
 When a
centerline and a hidden line
project at the same place, draw the hidden
line.
Refer to Figure 5-20A.
72
Multi-View
Drawing
Hidden Lines
 When a
hidden line crosses a visible line,
do not cross the visible line with a dash.
Refer to Figure 5-20B.
73
Multi-View
Drawing
Hidden Lines
 When hidden
lines cross, the nearest
hidden line has the “right of way”
Draw the nearest hidden line through
a space in the farther hidden line.
74
Multi-View
Drawing
Centerlines
Multi-View Drawing
75
Centerlines
 Centerlines
are special lines used to locate
views and dimensions.
76
Multi-View
Drawing
Centerlines
 Primary
centerlines
Locate the center on symmetrical
views in which one part is a mirror
image of another.
Are used as major locating lines to
help in making the views.
They are also used as base lines for
dimensioning.
Are drawn first.
77
Multi-View
Drawing
Centerlines
 Secondary
centerlines are used for drawing
details of a part
78
Multi-View
Drawing
Precedence of Lines
Multi-View Drawing
79
Precedence of Lines
 The
following priority of lines exists:
1. Visible lines.
2. Hidden lines.
3. Cutting-plane lines.
4. Center lines.
5. Break lines.
6. Dimension and extension lines.
7. Section lines (crosshatching).
80
Multi-View
Drawing
Curved Surfaces
Multi-View Drawing
81
Curved Surfaces
 Some
curved surfaces, such as cylinders
and cones do not show curved surfaces in
all views.
82
Multi-View
Drawing
Curved Surfaces
A
cylinder with its axis perpendicular to a
plane will show as a circle on that plane
and as a rectangle on the other two planes.
83
Multi-View
Drawing
Curved Surfaces
A
cylinder with its axis perpendicular to a
plane will show as a circle on that plane
and as a rectangle on the other two planes.
84
Multi-View
Drawing
Curved Surfaces
 The
holes may be thought of as negative
cylinders
In mathematics, negative means an
amount less than zero.
A hole is a “nothing” cylinder, but it
does have size.
85
Multi-View
Drawing
Cones
A
cone appears as a circle in one view.
 It appears as a triangle in the other view.
86
Multi-View
Drawing
Cones
view of a frustum of a cone appears as
two circles
In the top view, the conical surface is
represented by the space between
the two circles.
 One
87
Multi-View
Drawing
Cones
 Cylinders,
cones and frustums of cones
have single curved surfaces.
The appear as circles in one view and
straight lines in another.
88
Multi-View
Drawing
Deciding Which Views To Draw
Multi-View Drawing
89
Deciding Which View to Draw
 Six
views are not needed to describe most
objects.
 Usually
90
three views are sufficient.
Multi-View
Drawing
Deciding Which View to Draw
 Most
pieces can be recognized because
they have a characteristic view.
 This
is the first view to consider, and
usually is the first view to draw.
 Next, consider
the normal position of the
part when it is in use.
91
Multi-View
Drawing
Deciding Which View to Draw
 Views with
the fewest hidden lines are
easiest to read, and require less time to
draw.
92
Multi-View
Drawing
Deciding Which View to Draw
 The
main purpose of drawing views is to
describe the shape of the object.
 It
is a waste of time to make more views
than are necessary to describe the object.
93
Multi-View
Drawing
Deciding Which View to Draw
 Some
parts can be described in only one
view.
Figure 5-23 A.
Sheet material: plywood
Parts of uniform thickness
The
94
thickness can be given in a note.
Multi-View
Drawing
Deciding Which View to Draw
95
Multi-View
Drawing
Deciding Which View to Draw
96
Multi-View
Drawing
Deciding Which View to Draw
97
Multi-View
Drawing
Deciding Which View to Draw
 Some
parts can be described in only one
view.
Compare 5-24 C and D.
98
Multi-View
Drawing
Deciding Which View to Draw
 Some
parts can be described in two views.
Figure 5-25 A, B, C, D, E.
99
Multi-View
Drawing
Deciding Which View to Draw
100
Multi-View
Drawing
Deciding Which View to Draw
101
Multi-View
Drawing
Deciding Which View to Draw
 Examples
of parts that can be drawn in two
views:
Figure 5-26 A - F.
102
Multi-View
Drawing
Deciding Which View to Draw
 Long
and narrow objects may suggest top
and front view.
 Short
and broad objects may suggest top
and right-side views.
 Right
side is preferred over left-side when a
choices is available.
 Top view is preferred over bottom view
when a choice is available.
103
Multi-View
Drawing
Placing Views
Multi-View Drawing
104
Placing Views
 The
size of the drawing sheet should allow
enough space for the number of views
needed to give a clear description of the
part.
 The
method for determining the positions
of the views is the same for any space.
105
Multi-View
Drawing
Placing Views
 The
“working space” of a drawing is the
area inside the border.
 Objects are
the border.
never drawn directly touching
 Objects are
drawn so there is a space
between the object and the border line.
Refer to Figure 5-28.
106
Multi-View
Drawing
Placing Views

1. Measure the available drawing area using the scale of
the drawing.

2. Subtract out the space occupied by the object
 Horizontal:
Vertical:
Front View
 Right side View
Front View
Top View


3. Divide the remaining area by 4
 Put one part each
On left of Front View
 On right of Front View

On left of Right Side View
 On right of Right Side View

107
Multi-View
Drawing
Placing Views
 Converting
decimals to fractions.
 1. Use page 699 in text
Look up decimal
Look to left to find equivalent fraction
 2.
Convert fractions to 12ths of an inch
0.38 = 3/8
3/8 = x/12
8x = 36
x = 4.5 /12
108
Multi-View
Drawing
Figure 5-28
109
Multi-View
Drawing
Figure 5-29
110
Multi-View
Drawing
Placing Views
 1.
Add the width and the depth of the
object.
111
Multi-View
Drawing
Placing Views
 1.
Add the width and the depth of the
object.
 For the Base, Fig 5-63, p152,
The width is: 7.50”
The height is: 2.25” + 1.62”
The depth is: 3.25”
Width
112
+ depth = 7.50 + 3.25 = 10.75
Multi-View
Drawing
Placing Views
 2.
Subtract this total from the width of the
drawing space.
Refer to Figure 5-30.
A space of about 1” is commonly left
between the Side View and the Front
View.
Space may be larger or smaller,
depending upon the shapes of the
views.
113
Multi-View
Drawing
Figure 5-30
114
Multi-View
Drawing
Placing Views
 2.
Subtract this total from the width of the
drawing space.
 For the Base, Fig 5-63, p152,
Drawing Space width =
11” - 0.25” - 0.25” = 10.5” max.
Width
115
+ depth = 7.50 + 3.25 = 10.75
Multi-View
Drawing
Placing Views
 3.
Add the height and the depth of the
object.
 4.
Subtract this total from the height of the
drawing space.
 5.
116
Divide the remaining space evenly.
Multi-View
Drawing
Figure 5-30
117
Multi-View
Drawing
Locating and Transferring
Measurements
Multi-View Drawing
118
Locating Measurements
 Measurements
made on one view can be
transferred to another.
 This process also insures accuracy.
Refer to Figure 5-33.
119
Multi-View
Drawing
Locating Measurements
 1.
Draw upward from the Front view to
locate width measurements in the Top
view
Draw downward from the top view to
locate width measurements on the
Front view.
120
Multi-View
Drawing
Locating Measurements
 2.
Draw a light line across to the Side view
from the Front view to locate height
measurements
Use a similar method to project height
measurements from the side view to
the front view
121
Multi-View
Drawing
Locating Measurements
 Height
view.
of Front view - transfer to Right-side
 Depth
measurements show as vertical
distances in the Top view and as horizontal
distances in the the Right-side view.
122
Multi-View
Drawing
Locating Measurements
123
Multi-View
Drawing
Locating Measurements
124
Multi-View
Drawing
Locating Measurements
 3.
Depth measurements show as
Vertical distances - Top view
Horizontal distances - Right-side view
 To transfer these measurements use
Arcs
45o triangle
Dividers
Scale
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Using Arcs to Transfer
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Using Scale to Transfer
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Using 45 Line to Transfer
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Summary of Steps
 Follow
a step-by-step method to insure
accuracy
 Carry all views along together
 Do not attempt to finish one view before
starting the others
 Use a hard lead pencil (4H or 6H) and light,
thin lines for preliminary (layout) lines
 Use F, HB or H for final lines
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Summary of Steps
1. Consider the Characteristic View first.
2. Determine the number of views.
3. Locate the views.
4. Block in the views with light, thin layout
lines.
5. Lay off the principal measurements.
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Summary of Steps
6. Draw the principal lines.
7. Lay off the measurements for details such
as centers for arcs, circles and ribs.
8. Draw the circles and arcs.
9. Draw any additional lines needed to
complete views.
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Summary of Steps
10. Darken the lines where necessary to
make them sharp and black and of proper
thickness
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