1. PROJECTIONS

2. PROJECTIONS

3. Perspective Projection
Parallel projection
Perspective Projection

4. Orthographic Projection (Multiview Projection)4

5. Different Viewpoint

6. Orthographic Projection

7. Standard 2D views

8. The Principal Dimensions of an Object

9. Third Angle Projection First Angle Projection
USA, Canada
First Angle Projection
Europe, Asia

10. Third Angle Projection First Angle Projection
USA, Canada
First Angle Projection
Europe, Asia

11. Standard Views of Primitive Solids

12. View Orientation
Good orientation
Poor orientation

13. Select the most descriptive views
Use minimum number of views to describe the object

14. Conventional Practices - Intersections

15. 45o line drawn from point O
Miter Lines
Miter lines are used to transfer depth information.
45o line drawn from point O O
Standard multiviews

16. Fillets, Rounds & Chamfers

17. Top view

19. Edge Lines – Principal & Inclined
Principal lines appear
vertical, horizontal
or as point views.
Inclined lines appear
inclined in one view. 2

20. Oblique line appears inclined in all views
Edge Lines – Oblique
Oblique line appears inclined in all views

21. Principal Planes Principle planes are parallel to principal
orthographic planes

22. Inclined Planes Inclined planes are perpendicular to two
opposite orthographic
planes.

23. Oblique Planes Oblique planes are neither parallel nor perpendicular
to any principal
orthographic planes.

24. Type of Planes
Oblique
Principal
Inclined

25. Edge View of a Plane
Principal planes appear in true size in one plane and as an edge view in the other two planes.