2. Section 2 Drafting Techniques and Skills
Chapter 10
Section Views
Section 2 Drafting Techniques and Skills

3. Objectives Visualize a section view along a cutting plane.
Construct section views.
Draw various types of sections.
Apply conventional drafting practices in sectioning.
Describe how section views are created in CAD drafting.
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4. Section View Used to show interior detail.
Indicated by cutting-plane line.
Arrowheads specify viewing direction.
Labels and titles commonly used for identification.
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5. Section View
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6. Conventions for Cutting-Plane Lines
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7. Placement of Section Views
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8. Section Lines Drawn thin and parallel with uniform spacing.
Also called crosshatching.
Drawn in CAD with the Hatch command.
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9. Conventions for Section Lines
Normally drawn at 45.
Angle reversed or varied for adjacent parts.
Spacing between lines normally 1/8 to 3/16.
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10. Hidden Lines in Section Views
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11. Section View Conventions
Object lines may be omitted to save time.
Features normally revolved to improve clarity.
(American National Standards Institute)
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12. Types of Section Views Full section Half section Revolved section
Removed section
Offset section
Broken-out section
Aligned section
Thin section
Auxiliary section
Partial section
Phantom section
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13. Full Section View
Obtained by passing cutting plane through entire object.
Typically used in place of regular view to show details.
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14. Half Section View
Obtained by passing cutting planes at right angles along axes.
One-quarter of object removed.
Internal and external features shown.
Useful for symmetrical objects.
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15. Half Section View (Cont.)
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16. Revolved Section View
Obtained by passing cutting plane through part axis or centerline.
Used to show cross sections and common features.
May be shown with break lines or placed “inside” outline.
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17. Removed Section View Similar to revolved section.
Placed away from normal views.
Labeled with title to identify cross section.
May have different scale to show detail.
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18. Offset Section View
Obtained by “stepping” cutting plane through object features.
Shows sectioned features in one plane.
Useful for details lying in different planes.
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19. Offset Section View (Cont’d)
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20. Broken-Out Section View
Drawn as part of regular view.
Break lines indicate section limits.
Used where only partial section is needed.
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21. Aligned Section View
Shows features in different planes rotated into cutting plane.
Used when true projection may be confusing.
Common for features such as spokes and ribs.
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22. Thin Section Solid material shown instead of section lining.
Adjacent features separated by space.
Common for structural parts and sheet metal.
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23. Auxiliary Section View
Shown in normal position.
Used to clarify important details.
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24. Partial Section View
Shows necessary detail without drawing a complete view.
Used to save drafting time.
(General Dynamics, Engineering Dept.)
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25. Phantom Section View
Used to show internal details along with outer construction.
Not common in industrial applications.
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26. Sectioning Standard Parts
Parts perpendicular to cutting plane are shown sectioned.
Parts parallel to cutting plane are not sectioned.
Applies to shafts, bolts, nuts, and pins.
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27. Conventional Sectioning Practices
Conventional breaks
Intersection conventions
Sectioning practices for regular machine parts
Outline sectioning
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28. Conventional Breaks Used for long parts with uniform sections.
“S” breaks common for bar and tubing sections.
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29. Drawing “S” Breaks
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30. Drawing “S” Breaks
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31. Conventions for Intersections in Section Views
For small offsets, intersection is drawn without curve.
For larger offsets, curve is used.
(American National Standards Institute)
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32. Sectioning Practices for Regular Machine Parts
Common parts are not sectioned when cutting plane extends along length.
Applies to ribs, webs, lugs, and gear teeth.
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33. Outline Sectioning Shown along borders of part.
Used for large parts to save time.
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34. Material Symbols for Section Lining
Used when drawing shows multiple materials.
General purpose sectioning typically sufficient for most applications.
Materials usually specified by name in list.
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35. Standard Material Symbols
(John Deere & Co.)
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36. Hatching in CAD Created with Hatch command.
Material patterns provided by program.
Hatch boundary defines sectioned area.
Settings specify angle, scale, and spacing.
Editing tools typically provided.
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37. CAD Hatch Patterns
(Autodesk, Inc.)
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38. Review Questions 1. A section view is indicated by a(n) _____ line.
A. dimension
B. extension
C. border
D. cutting-plane
D. cutting-plane
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39. Review Questions
2. _____ at the ends of the cutting-plane line are used to indicate the direction in which the section is viewed.
Arrowheads
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40. Review Questions
3. The section view should be placed _____ the cutting-plane line arrows.
behind
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41. Review Questions
4. The cutting plane for a(n) _____ section is stepped through different planes on the object.
A. half
B. full
C. offset
D. revolved
C. offset
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42. Review Questions
5. In a(n) _____ section, features are rotated into the cutting plane to avoid the confusion of a true projection.
A. aligned
B. offset
C. revolved
D. auxiliary
A. aligned
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43. Review Questions
6. _____ sectioning is a practice in which section lines are only shown along the borders of a part.
Outline
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44. Review Questions
7. The conventional breaks for cylindrical bars and tubing are known as _____.
“S” breaks
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45. Review Questions
8. The _____ command is used to create section lining.
A. Pan
B. Hatch
C. Polyline
D. Xline
B. Hatch
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