1. TA 101: Technical Arts 2015-16 II Dr. Prishati Raychowdhury
Department of Civil Engineering
IIT Kanpur
Office: FB 336; Phone: 6692

2. Isometric Projection & Oblique Projection
Lecture 8
Isometric Projection & Oblique Projection

3. Notice Make-up Lab on Friday, 29th January, 2016
[For Tuesday Batches: B1, B2, B3]
Time and venue remains the same:
[Northern Drawing Hall, 10 am- 1 pm]

4. Isometric view: Example 1D1 D1 L2 L2 H2 L2 D1 H1 H3 L1 H2 H1 L2 L1 H3 D1

5. Use of GRID Sheets with 30o lines

6. Example 2: Using Isometric GridsH D
Non-isometric Plane
Isometric Plane H L D
Normal Grid
Isometric Grid

7. Isometric View: Example 3

8. Isometric View: Example 48

9. Offset/Coordinate Method
When an object is made up of planes at different angles (i.e. most of the edges are non-isometric lines), it is better to locate the ends of the edges by offset method, rather than boxing
Perpendiculars are extended from each end point of the edge to an isometric reference plane
These perpendiculars, which are isometric lines, are located on the drawing by isometric coordinates

10. Example 1: Pentagonal PyramidEF OF
O’F DF CF BF AF O P S R Q A B C D E P S R Q A B C D E O O’
Isometric View of Pentagonal Pyramid

11. Example 2: Truncated Triangular PyramidO O p p A A C q O B C B q

12. Next Topic
Oblique Projections

13. Oblique Projection OBLIQUE ORTHOGRAPHIC ISOMETRIC Front Face in
TRUE SHAPE
OBLIQUE
ORTHOGRAPHIC
ISOMETRIC

14. Plane of projection PARALLEL PROJECTORS OBLIQUE (NOT PERPENDICULAR)
TO THE PLANE
Plane of projection

15. Oblique Projections Details along depth axis True Shape 300 to 600
Isometric
Oblique
The oblique method is mainly used for objects with circular or curved features only one face or on parallel faces
For objects of this type the oblique is easy to draw and dimension
This is an widely used pictorial view

16. Oblique Projections
An oblique view is formed by parallel projectors that make an angle other than 900 with the projection plane
The object is not rotated or tilted and has a major face parallel to projection plane so that the front face of the object is seen in its true shape
The height and width of the object remain at 900 to each other (front face)
The details of the object along the depth are shown along a depth axis taken at an arbitrary angle (normally 300 or 450)
The depth direction may be taken either left or right, and up or down

17. Steps Draw a rectangle –overall width and height of the object
Extend parallel lines from each corner of the box back at an angle (30o or 45o)
Mark the extension lines at a point equal to the depth of the object
Connect the depth of lines to form a box
Add any details such as holes, notches, onto the front view (True size & True Shape)
Extend the details the depth of the object
Complete sketch by darkening in the object

18. Oblique Drawing Example 1
300

19. Oblique Drawing Example 1

20. Thank you..