ENGINEERING DRAWING & CAD

DCC10012 - ENGINEERING DRAWING AND COMPUTER AIDED DRAFTING DEPARTMENT OF CIVIL ENGINEERING
SIMPLE NOTES AND EXCERCISES

ISOMETRIC SECTION FLOOR PLAN

600 600 150MM X 150MM 'TUNJUK LANGIT'
75MM X 50MM WINDOW COPING
3000 CONCRETE TILES ROOFING AT 30° PITCH
6MM THICK GLASS CEILING LEVEL
225MM X 20MM HW FASCIA BOARD
1200MM X 1200MM 2 PANEL
HW HINGES WINDOW 50MM X 100MM DOOR FRAME
25MM X 50MM DOOR STOPS
50MM X 100MM WINDOW FRAME 75MM x 50MM LIGHTWEIGHT DOOR COPING
8MM THICK GLASS
450 450 900 900MM X 2100 HW PANEL DOOR
38MM THICK WOODEN PANEL
150MM BRICKWALL C/W PLASTER BOTH SIDE

3300MM X 3300MM X 450 CONCRETE FLOOR

3000 1650 1200
600 3300
3000
LEFT SIDE VIEW 3300

FRONT VIEW

mrm '65

CIVIL ENGINEERING DEPARTMENT

ENGINEERING DRAWING

TOPIC 3

ISOMETRIC AND OBLIQUE DRAWING
PLO 5 - Apply appropriate techniques, resources, and modern engineering and
IT tools to well-defined engineering problems, with an awareness of the limitations

DCC10012-cad/ mrm’65|

mrm 65 ISOMETRIC DRAWING

In an isometric drawing, the object vertical line are drawn verticlly, and the horizontal line
in the width and depth plane are shown at 30 degrees to the horizontal. When drawn under
these guidlines, the line parallel to these three axes are at their true (scale) length. Line that
are not parallel axes will not of their true length.

Depth Width

ISOMETRIC AND OBLIQUE DRAWING 30
High 20

30 R5 10
40

A An Isometric View Dimensioning

An Isometric View Angle

C1

40

C3 C4

C3 C2 C3 10 20 30 X
C2 C2 10

C4 C4 C1 25 25
C1 X

Isometric circle using Four Centre Method Drawing an angle in Isometric View

10 Y
Y

D (Depth)

10 40
7 5 8 10
A
10 10 5 5 10 10

30

20

50 40 10

Orthographic Projection

11

mrm 65 OBLIQUE DRAWING

In this system, the main view is drawn as an orthographic projection (front view) and the
side view are represented on inclined planes. The angle between the orthogonal and
inclined plane is 45 degrees. The oblique view can be shown into three method:

a. Cavalier Oblique ( D )
b. Cabinet Oblique ( 1/2 D )
c. Common Oblique ( 3/4 D )

ISOMETRIC AND OBLIQUE DRAWING 40
30 10

30
20

5
30
30

7.5

R5 R5 R5
30 30 30

Cavalier Oblique (D) Cabinet Oblique (1/2 D) Common Oblique (3/4D)

High
Depth
R5
Width

Oblique Axis

D (Depth)

10 10 5 5 10 10

30 7 5 8 10

20

50 40 10

Orthographic Projection
12

mrm 65 DIMENSIONS

The purpose of dimensioning is toprovide a clear and complete description of an object.
A complete set of dimensions will permit only one interpretation needed to construct the part.

Dimensioning should follow these guidelines:
a. Accuracy : correct values must be given
b. Clearness : dimensions must be placed in appropriate position
c. Completeness : nothing must be left out and nothing duplicated
d. Readability: the appropriate line quality must be used for legibility

Dimensioned Drawing : R15

1.5 mm Gap 3-5 mm extend Extension Line
Arrow head
40 20 20 20 20 Dimension Line

Text / Dimension

DIMENSIONS 12 mm 15 x 3x
8 mm 65 Arrow head size
3 mm 85

Linear Dimension 39 Aligned Dimension

40

Angular Dimension

58
Linear Dimension

Types of dimension line symbols : 34 34
Oblique Open 30
34 34

Dot Architectural thick
9
9
9
9

13