The document discusses engineering drawing skills like lettering, line types, orthographic views, and dimensioning. It covers topics such as visible versus hidden lines, center lines, construction lines, first angle and third angle orthographic projections, and techniques for dimensioning objects. Examples are provided of orthographic views showing front, top, and side views and the use of construction lines to develop views.

1. REVIEWS

2. Engineering Drawing Skills Lettering..good writing Line Types..clear between thick and thin lines Orthographic Views Patience See the example drawings in the notes.

3. Line Types Visible Line (thick) Hidden Line (thick) Center Line (thin) Dimension Line (thin) Construction Line (thin)

4. Line Types

5. Sketching Techniques

6. Todays lecture is about... ISOMETRIC VIEW ORTHOGRAPHIC VIEW

7. Orthographic Projection

8. THIRD WEEK ORTHOGRAPHIC Introduction to orthographic view. First angle projection view. Third angle projection view. Projection view symbols. Selection of direction views. Dimensioning for orthographic .

9. Describing an Angle Bracket

10. Orthographic Projection Orthographic drawings represent three dimensional objects in three separate views arranged in a standard manner.

11. Orthographic Views You can adequately describe most objects with three orthographic views. Front Top Right

12. Converting to Orthographic

14. Orthographic Views Hidden lines Centre line

15. The Glass Box Approach

16. Opening the Box

17. Final Views

18. Construction of Views CONSTRUCTION LINES

19. Object for exercise

20. Solution

21. Solution

22. Solution

23. First Angle Projection Introduce in Europe as the earlier method of engineering drawing. The object is as though in the first quarter ( 0 0 ~ 90 0 )

24. First Angle Projection Symbol used in Engineering Drawing

25. First Angle Projection Based on 3 basic views :- Plan view (seen from the top of the object) Front view (seen from the front of the object) Side view (seen from the side of the object) The shadows of the object are cast onto the plane behind the object

26. First Angle Projection The shadows of the object are cast onto the plane behind the object SIDE VIEW FRONT VIEW PLAN VIEW

27. Third Angle Projection Introduce in USA, this standard is being widely used till today The object is as though in the first quarter ( 180 0 ~ 270 0 )

28. Third Angle Projection The standard symbol

30. Orthographic Views

31. Third Angle Projection Based on 3 basic views :- The plan view (as seen from the top of the object) The front view (as seen from the front of the object) The side view (as seen from the side of the object) The shadows of the object are shown onto the plane in front of the object PLAN SIDE VIEW FONT VIEW

32. Third Angle Projection The shadows of the object are shown onto the plane in front of the object PLAN SIDE VIEW FRONT VIEW

34. Theory of Dimensioning -Techniques and Conventions Object is made of several parts Position (P) Size (S) Each feature is dimensioned once For each feature, dimension positioned where its shape shows No Redundancy