1. SECTION VIEWS

2. This is done by using the technique of drawing…
Can you guess what is inside of this box?
This is done by using the technique of drawing…
SECTION VIEWS
If you had the Invisible Women’s powers you could make the box invisible and see what is hidden from view.
How can a Designer show on a drawing what is hidden from view?

3. A Section Drawing of a V-Type Four Stroke Diesel Engine
Section Views: are used to show inside features of objects that would otherwise be unseen.
A Section Drawing of a V-Type Four Stroke Diesel Engine

4. Hand out Unit organizers
The Big Picture
The Unit Organizer
Techniques used on Working Detail Drawings
LAST UNIT/ Experience
Basic Dimensioning
CURRENT UNIT
PRODUCE SECTION VIEW DRAWINGS
NEXT UNIT/ Experience
Auxiliary Views
Inside feature are not visible
Principles & Exceptions
Required When
When omitted
Section Views
Have many types
Are identified by
Types of Section Views
Are
Labeled by
Section Lines
(X-Hatch)
Hand out Unit organizers
C.P.L. Elements & Placement
What determines the need for a section view?
What are some types of section views?
How are webs, ribs and spokes represented in a section view? And why?
UNIT SELF-TEST
QUESTIONS
UNIT RELATIONSHIPS

5. The Unit Organizer Section Views Basic Dimensioning
The Big Picture
Techniques used on Working Detail Drawings
LAST UNIT/ Experience
Basic Dimensioning
CURRENT UNIT
PRODUCE SECTION VIEW DRAWINGS
NEXT UNIT/ Experience
Auxiliary Views
UNIT SCHEDULE
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
Inside feature are not visible
Principles & Exceptions
Required When
Section Views
When omitted
Have many types
Are identified by
Labeled by
Are
Types of Section Views
Section Lines
(X-Hatch)
C.P.L. Elements & Placement
What determines the need for a section view?
What are some types of section views?
How are webs, ribs and spokes represented in a section view? And why?
UNIT SELF-TEST
QUESTIONS
UNIT RELATIONSHIPS

6. Objectives Explain why section views are necessary.
Explain and accurately draw a cutting- plane line and X-hatch (cross-hatch) lines.
Recognize and appropriately use the following section view types on a drawing: Full section, Half section and Offset section.

7. Why Use Section Views?
Section Views: are used to show inside features of objects that would otherwise be unseen.

8. Why Use Section Views?
How can we dimension to these interior features without using the hidden lines?

9. Cutting-Plane Lines (CPL) Cross-Hatch Lines (X-Hatch)
and
Cross-Hatch Lines (X-Hatch)

10. CUTTING PLANE LINESTYLES
This course
Thick line
Viewing
direction
ANSI
standard
Thick line
Viewing
direction
JIS & ISO
standard
Thin line
Viewing
direction

11. SECTION LINING Section lines or cross-hatch lines are used to
indicate the surfaces that are cut by the cutting
plane.
Section
lines
Drawn with thin dark lines
usually at a 45 degree angle.

12. SECTION LINES SYMBOLS
The section lines are different for each of material types.
For practical purposes, the cast iron symbol is used most often for any materials.
Cast iron,
Malleable iron
Steel
Concrete
Sand
Wood

13. SECTION LINING PRACTICE
The spaces between lines may vary from .125 inches
for small sections to .25 inches for large sections.
COMMON MISTAKE

14. SECTION LINING PRACTICE
Section lines should not be drawn parallel or perpendicular to contour of the view.
COMMON MISTAKE

15. Types of Section Views

16. FULL SECTION VIEW
The view is made by passing the straight cutting plane completely through the entire part.

17. HALF SECTION VIEW
The view is made by passing the cutting plane halfway through an object and removing a quarter of it.

18. HALF SECTION VIEW
A center line is used to separate the sectioned half from the unsectioned half of the view.
Hidden lines are omitted in the unsectioned half of the view.

19. OFFSET SECTION VIEW
The view is made by passing the bended cutting plane completely through the part.
Do not show the edge views
of the cutting plane.

20. The Unit Organizer Section Views Basic Dimensioning
The Big Picture
Techniques used on Working Detail Drawings
LAST UNIT/ Experience
Basic Dimensioning
CURRENT UNIT
PRODUCE SECTION VIEW DRAWINGS
NEXT UNIT/ Experience
Auxiliary Views
UNIT SCHEDULE
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
Inside feature are not visible
Principles & Exceptions
Required When
Section Views
When omitted
To show the inside features of mech. parts
Have many types
Are identified by
Labeled by
Are
Types of Section Views
Section Lines
(X-Hatch)
C.P.L. Elements & Placement
Full section
Half section
Offset section
Surfaces
Direction
Spacing
Angle
Material specifications
Line types
Arrows
Labeling
What determines the need for a section view?
What are some types of section views?
How are webs, ribs and spokes represented in a section view? And why?
UNIT SELF-TEST
QUESTIONS
UNIT RELATIONSHIPS

21. Types of Section Views
(continued)

22. Objectives
Recognize and appropriately use the following section view types on a drawing: Removed section, Revolved section and Broken-out section.
Explain how hidden lines are used in section views.
Accurately draw Ribs, Webs, Spokes and Lugs in section views.

23. REMOVED SECTION VIEW Example : Revolved vs. removed sections.
Revolved section
Removed section

24. REMOVED SECTION VIEW
Example : Situation that removed section is preferred.
Poor
Preferred
Too messy !!

25. REMOVED SECTION VIEW Example : Multiple removed section views B A
SECTION B – B
SECTION A – A

26. REVOLVED SECTION VIEW
Basic concept

27. REVOLVED SECTION VIEW Steps in construction Step 1 Given
Edge view of
cross-section
Step 1
a. Assign position of cutting plane.
b. Draw axis of rotation in front view.

28. REVOLVED SECTION VIEW Steps in construction Step 2 Given
a. Transfer the depth dimension to
the front view.

29. REVOLVED SECTION VIEW Steps in construction Step 3 Given
a. Draw the revolved section.
b. Add section lines.

30. REVOLVED SECTION VIEW
Steps in construction
Given
FINAL PICTURE

31. REVOLVED SECTION VIEW Placement of revolved section
1. Superimposed to orthographic view.
2. Break from orthographic view.
Break
Superimposed

32. BROKEN-OUT SECTION VIEW
The view is made by passing the cutting plane normal to the viewing direction and removing the portion of an object in front of it.

33. EXAMPLE : Comparison among several section techniques

34. The Unit Organizer Section Views Basic Dimensioning
The Big Picture
Techniques used on Working Detail Drawings
LAST UNIT/ Experience
Basic Dimensioning
CURRENT UNIT
PRODUCE SECTION VIEW DRAWINGS
NEXT UNIT/ Experience
Auxiliary Views
UNIT SCHEDULE
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
Inside feature are not visible
Principles & Exceptions
Required When
Section Views
When omitted
To show the inside features of mech. parts
Have many types
Are identified by
Labeled by
Are
Types of Section Views
Section Lines
(X-Hatch)
C.P.L. Elements & Placement
Full section
Half section
Offset section
Surfaces
Direction
Spacing
Angle
Material specifications
Line types
Arrows
Labeling
Removed section
Revolved section
Broken-out section
Aligned section
What determines the need for a section view?
What are some types of section views?
How are webs, ribs and spokes represented in a section view? And why?
UNIT SELF-TEST
QUESTIONS
UNIT RELATIONSHIPS

35. TREATMENT OF HIDDEN LINES
Hidden lines are normally omitted from section
views.

36. The Unit Organizer Section Views Basic Dimensioning
The Big Picture
Techniques used on Working Detail Drawings
LAST UNIT/ Experience
Basic Dimensioning
CURRENT UNIT
PRODUCE SECTION VIEW DRAWINGS
NEXT UNIT/ Experience
Auxiliary Views
UNIT SCHEDULE
2-col note vocab
Hand-outs
worksheets
Jeopardy Game
Drawings
Quizzes
Unit Test
Inside feature are not visible
Principles & Exceptions
Required When
Section Views
When omitted
To show the inside features of mech. parts
Ribs, Webs , Spokes, hidden lines & dimensions
Have many types
Are identified by
Labeled by
Are
Types of Section Views
Section Lines
(X-Hatch)
C.P.L. Elements & Placement
Full section
Half section
Offset section
Surfaces
Direction
Spacing
Angle
Material specifications
Line types
Arrows
Labeling
Removed section
Revolved section
Broken-out section
Aligned section
What determines the need for a section view?
What are some types of section views?
How are webs, ribs and spokes represented in a section view? And why?
UNIT SELF-TEST
QUESTIONS
UNIT RELATIONSHIPS

37. Sectioning Principles

38. RIBS AND WEBS
Ribs and Webs are thin, flat features of an object used for bracing or adding strength.
Web
Rib
Rib

39. EXAMPLE : RIB Normal multiview drawing Normal section view
Section view drawing with convention

40. EXAMPLE : WEB : flatwise cut
Normal multiview drawing
Normal section view
Section view drawing with convention

41. EXAMPLE : WEB : crosswise cut

42. EXAMPLE : WEB : multiple section view

43. SPOKES
Spoke: One of several bars attaching a hub to the rim of a wheel
Hub
Hub
Spoke
Rim
Spoke
Rim

44. Misleading impression
EXAMPLE : SPOKE
Misleading impression

45. LUGS
Lug: An ear-like projection used for attachment.

46. LUGS
Lug: An ear-like projection used for attachment.

47. EXAMPLE : LUG

48. CONVENTIONAL PRACTICE
Omit the section lines on the section view of
Rib, Web and Lug, if the cutting plane is passed flatwise through.
Spoke, if the cutting plane is passed longwise through.

49. Aligned Section

50. Objectives
RXxxXXx
XxxxxxxxxxxxxxxxXxxx
X xxx xxxxxxxxxxxx

51. DEFINITION Aligned section is a section view that is drawn
by imaginary rotating the object’s features
appeared in a principal view about symmetry
axis

52. Gives the impression that this holes are at unsymmetrical position.
Example : Hole
Gives the impression that this holes are at unsymmetrical position.

53. Example : Hole

54. Example : Rib

55. Example : Ribs & Holes

56. Example : Spoke & Keyway
Example : Aligned section of keyway

57. Example : Lug

58. Conventional Break

59. CONVENTIONAL PRACTICE
For long objects that have to draw in a small scale to fit them on the paper, it is recommended to remove its long portion (which contains no important information) and draw the break lines at the broken ends.

60. Example
SCALE 1:1

61. Example
SCALE 2:1

62. STANDARD BREAK LINES Rectangular cross section Cylindrical
Wood
Rectangular
cross section
Metal
Cylindrical
cross section
Tubular
cross section

63. TO DRAW CYLINDRICAL BREAK

64. not to scale dimensions
TO DIMENSION A BROKEN PART
f16
Typical
dimensioning
method
800
f16
800
not to scale dimensions