Republic
of the Philippines
PANGASINAN STATE UNIVERSITY
Urdaneta City, Pangasinan
COLLEGE OF ENGINEERING AND ARCHITECTURE
ISOMETRIC DRAWINGS
- The term "ISOMETRIC" comes from the Greek for "equal measure",
reflecting that the scale along each axis of the projection is the same
- a method for visually representing three-dimensional objects in two
dimensions in technical and engineering drawings.
- It is an axonometric projection in which the three coordinate axes appear
equally foreshortened and the angle between any two of them is 120
degrees.
Date Prepared by: Noted by: Recommending Approval: Approved by: Page:
Implemented:
July 16.2018 Simeon Rico, Jr., RLA, Sherwin Victor G. Galamgam, Resurreccion V. Garrote,
Architecture MScm Ph.D. RCE, MSCE
Date Revised: Department Chairman –Architecture College Dean, CEA Campus Executive Director
May 17-24 ,2018 Department
Republic of the Philippines
PANGASINAN STATE UNIVERSITY
Urdaneta City, Pangasinan
COLLEGE OF ENGINEERING AND ARCHITECTURE
- Isometric drawings establish a lower angle of view than plan oblique and
give equal emphasis to the three principal sets of planes. They preserve the
relative proportions of a subject or scene and are not subject to the distortion
inherent in oblique views.
Date Prepared by: Noted by: Recommending Approval: Approved by: Page:
Implemented:
July 16.2018 Simeon Rico, Jr., RLA, Sherwin Victor G. Galamgam, Resurreccion V. Garrote,
Architecture MScm Ph.D. RCE, MSCE
Date Revised: Department Chairman –Architecture College Dean, CEA Campus Executive Director
May 17-24 ,2018 Department
CONCEPT OF ISOMETRIC DRAWING
3 dimensional drawing (width, height and depth)
Showing 3 views (top, front and side)
Base line 30° from the horizontal plane
A
A
C
B
F
C
E B G
G F
D D
E
OBJEK A
OBJEK A OBJEK A
ISOMETRIC AXIS
Normal axis Reversed axis
Horizontal axis
CHRACTERISTICS OF ISOMETRIC DRAWING
Isometric lines –
parallel to isometric
axis
Non-isometric lines-
lines that not parallel
to isometric axis
STEPS IN CONSTRUCTING AN ISOMETRIC
DRAWING
Step 1
Sketch a thin horizontal line XY.
X Y
Step 2
Sketch a thin vertical axis AB perpendicular to the
given line XY and forming two 90 degrees angles.
B
X A Y
Step 3
Sketch a thin 30 degree left cross axis AC
B
X A Y
Step 4
Sketch a thin 30 degree right cross axis AD
B
C D
X A Y
Step 5
Mark out distances to represent the width,
height and depth/thickness
B
C D
X A Y
Step 6
Connect CE which is parallel to the vertical
axis EB which is parallel to AC
E B
C D
D
C
X A Y
Step 7
Connect DF which is parallel to the vertical
axis BF which is parallel to AD
E F
B
C D
X A Y
Step 8
Complete the drawing
E F
B
C D
X A Y
Orthographic to Isometric
• Hints for Isometric Sketching
Isometric & Orthographic Sketching
●
Identify major features and overall dimensions
●
Use clean, crisp strokes
●
Do not use straightedges or scales when sketching
●
Start by drawing a bounding box, using construction lines
●
Only measure dimensions along the primary axes
●
Do not directly transfer angles from a multiview to a
pictorial
●
Use light construction lines to locate vertices and edges
●
Sketch faces roughly in this order:
●
Normal faces on the perimeter of the bounding box
●
Normal faces in the interior of the bounding box
●
Inclined faces
●
Oblique faces
●
Darken all object lines
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Set up Isometric Axis using
1 vertical line and 2 lines at
30 degrees from horizontal
Estimate the overall width
height and depth of the
object, and sketch the
edges of a block that would
completely enclose the
object
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Sketch the outline
of the front face
using lines parallel
and equal in length
to the two previous
height and width
edges
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Sketch the outlines
of the top and side
faces using the
same basic
procedure as used
for the front face
Begin sketching
start/end points of
major features
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Begin darkening
major features as
they are developed
Locate start/end
points of additional
and smaller features
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Locate and sketch start/
end points for non-
isometric lines such as
the angled surface
Sketch and darken the
non-isometric features
GE 121 – Engineering Design - 2009
Ortho to Iso
Isometric & Orthographic Sketching
Completed
Isometric
Sketch with
construction
lines erased
GE 121 – Engineering Design - 2009
Republic of the Philippines
PANGASINAN STATE UNIVERSITY
Urdaneta City, Pangasinan
COLLEGE OF ENGINEERING AND ARCHITECTURE
Date Prepared by: Noted by: Recommending Approval: Approved by: Page:
Implemented:
July 16.2018 Simeon Rico, Jr., RLA, Sherwin Victor G. Galamgam, Resurreccion V. Garrote,
Architecture MScm Ph.D. RCE, MSCE
Date Revised: Department Chairman –Architecture College Dean, CEA Campus Executive Director
May 17-24 ,2018 Department
