1. ES 101 Engineering Graphics
Fall 2018
ES 101 Engineering Graphics
Gaurav
Assistant Professor
Civil Engineering

2. Mid Sem exam Not showing all construction lines
Different views not related
Construction lines too dark
Non-uniform line thickness
Lines that should be parallel/perpendicular were not so
Not using good writing practice
Writing inside the object when it can be avoided
Hidden lines going beyond object
Construction lines drawn as dashed lines
Thickness of hidden lines not same as object lines
Not using ruler for drawing lines / free hand sketching
Centre lines not crossing at small dash
Wrong measurements
Scale

3. Scale
Dimensions of large objects must be reduced to accommodate on standard size drawing sheet. Similarly in case of tiny objects dimensions must be increased.
1: 2
1: 0.5
Large Objects
Ex: Table or chair
Drawing Size
1:1
Ex: Keyboard of a computer
Small Objects
Ex: Circuit of a mobile phone

4. Scale
Representative Fraction, RF:
RF = 0.2 or 1/5 means the actual object is five times larger than the size shown on drawing Scale = 1:5
RF = 5 or 5/1 means the actual object is five times smaller than the size shown on drawing Scale = 1:0.2

5. 1 : R Scale Hence, the Scale is written as (Drawing : Real) i
Full Scale :1
Reduced Scale 1:R R>1.0
Enlarged Scale 1:R R<1.0
on Right is the Real size

6. Plane Scale For dimensions up to ONE decimal Example:
Scale of 1 cm = 1m to read decimeters
Maximum distance of 6 m
Show distance of 4 m and 6 dm
4 m 6 dm 10
METER 1 2 3 4 5
DECIMETER

7. Diagonal Scale For dimensions up to TWO decimals Example:
Scale of 1 cm = 1m to read centimeters
Maximum distance of 6 m
Show distance of 4 m and 46 cm 5 10
CENTIMETER
4 m 46 cm 10
METER 1 2 3 4 5
DECIMETER

8. Diagonal Scale: Example
Construct a diagonal scale of R.F. =1/500 to read up to 60 meters and to read millimeters on it. Show a length of meters on it. 5 10
MILLIMETER m
100
METER 10 20 30 40 50
CENTIMETER

9. Need of Sectioning
To show details of the interior of an object or the component parts of a assembled model.
The interior features are usually represented by hidden lines. A drawing with too many hidden lines may be confusing and difficult to understand.
One or more section views are drawn as if a portion had been cut away to reveal the interior.

10. Cutting Plane & Cutting Plane Line

11. Types of Cutting Plane Line
Viewing Direction
Section Identity
Viewing Direction
Section Identity

12. Viewing Direction

13. Visible Edges in Sectioning

14. Lines in Sectioning

15. Hidden Lines in Sectioning
Sometimes, hidden lines are necessary for clearness, and should be used in such cases.
The use of hidden lines in a section may sometime allow omitting a view.

16. Hidden Lines: Example
Hidden lines needed to omit a view

17. Hatching Preferred direction of hatching: 45.
Can also be 30, 60 or somewhere in between.

18. Hatching Same Object; same direction of hatching.
Different component of same material shall have different hatching though.

19. Materials Hatching

20. Types of Sectioning Full section Half section Broken-out section
Rotated section
Removed section
Assembly section

21. Full Section
Standard Multi-view
Full section view

22. Full Section

23. Full Section with Offset

24. Full Section with Offset

25. Full Section with Rotation

26. Half Section
Standard Multi-view
Half section view

27. Half Section

28. Broken-out section view
Standard Multi-view
Broken-out section view

29. Rotated Section

30. Rotated Section

31. Rotated Section

32. Removed Section

33. Removed Section

34. Assembly Section

35. Ribs and Webs

36. Shafts
No Sectioning of Shaft

37. No Sectioning of Spokes
Spokes and Arms
No Sectioning of Spokes
No Sectioning of Arms

38. Lugs and Ears

39. Other Conventions

40. Practice Problems From textbook: Problem 14-5 Problem 14-13

41. Practice Problem Draw multi-views Top-view should show the
through hole front-on
Show section X-X in front view
Show un-sectioned right view