engn103 engineering drawing orthographic … · triangle of sides 40mm, ... hexagon of side 25mm....
TRANSCRIPT
L E C T U R E 3
ENGN103 ENGINEERING DRAWING
ORTHOGRAPHIC PROJECTIONS
WHAT IS ORTHOGRAPHIC PROJECTION?
• Orthographic Projection is a method of
representing a three dimensional object on paper
using several two dimensional views.
• It is the international language of Engineers and
Designers
Front elevation Side elevation
Plan – Top view
ORTHOGRAPHIC PROJECTION- SIMPLE SHAPES
1. Rectangle of sides 50 x 35 mm resting on HP.
2. Rectangle of side 50 x 35 mm, with short edge on HP. 10mm
away from PP and 5mm away from VP.
3. Rectangle of side 50 x 35 mm, with short edge on HP. 10mm
away from PP and 5mm away from VP. Inclined at 30degree to
VP.
4. Rectangle of sides 50 x 35 mm, with one corner on HP. Making
30degree and 60degree with HP.
corner
Short edge
Long edge
ORTHOGRAPHIC PROJECTION- SIMPLE SHAPES
• Draw the orthographic projections:
1. Circle of radius 25mm resting on HP, 10mm away
from VP and PP.
2. Triangle of sides 40mm, 15mm and 35mm. 7.5mm
away from PP, 10mm away from VP and 7.5mm
above HP.
3. Hexagon of side 25mm. 10mm away from VP.
4. Rectangle of sides 35mmx60mm lying flat on HP. A
square of side 25mm is resting on the rectangle
with its corner on the center of the rectangle.
DRAW ORTHOGRAPHIC PROJECTIONS:
• Cube of side 45mm with a whole of 10mmx10mm in
the center of one of the sides.
• Triangular Pyramid of sides 30mm and height 55mm.
• A cone of base radius 20mm and height 40mm.
Resting on the corner
• A cylinder of base radius 15mm and length 55mm.
Resting on the side.
ORTHOGRAPHIC PROJECTION OF OBJECTS
Front elevation Side elevation
Plan – Top view Isometric view
Width Depth
Height
Width
He
igh
t
Depth
Depth
Wid
th
He
igh
t
FRONT ELEVATION SIDE ELEVATION
PLAN
FRONT ELEVATION SIDE ELEVATION
FRONT ELEVATION SIDE ELEVATION
PLAN
FRONT ELEVATION SIDE ELEVATION
PLAN
FRONT ELEVATION SIDE ELEVATION
PLAN
FRONT ELEVATION SIDE ELEVATION
PLAN
CENTERLINES
PRECEDENCE OF LINES
FRONT ELEVATION SIDE ELEVATION
PLAN
PLAN
SIDE ELEVATION FRONT ELEVATION