Multiview Drawings

1
Multiview Drawings

• Unit 8
• Page 89

2
Objectives

• Identify an orthographic projection.
• Select the best views to describe an object.
• Identify objects from an orthographic projection
  drawing.
• Identify the visualization rules of an
  orthographic projection drawing.

3
What is an Orthographic Projection?

• An orthographic projection is a multi-view
  drawing used to show all of the features of an
  object.
• Different views are set up in a systematic way to
  mentally connect them together.

4
Purpose of Orthographics

• Shows the true size and shape of the features of
  an object
• Provide certain information on how the object is
  to be made.

5
The Projection of Views

• Must be able to visualize the object as a whole
  and be able to mentally put the views together.
• Views are projected at right angles (90 Deg) to
  each other.
• There are 6 different views possible in an
  orthographic projection.

6
Possible Views

• Top

Front
Right Side
Left Side
Back
Bottom
7
Selection of Views

• Not all 6 views have to be shown in an
  orthographic projection drawing.
• Details are repeated in the top and bottom, right
  and left, and the front and back views.

8
Rules For Selecting Views

• 1. Only views that clearly describe the object
  are used.
• 2. Views that show the least hidden lines should
  be selected.
• 3. The object should be shown in its
  functioning position when possible.
• 4. The view that best describes the object
  should be selected as the front view.

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Visualization

• Visualization is the ability to form a mental
  picture of what an object is going to look like
  when its completed.
• You must compare the top, front, sides, back and
  bottom views to see what shapes the objects have
  in common.

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Visualization Rules

• 1. Scan briefly all views shown.
• 2. Study the front view for shape description.
• 3. Move from view to view to find similar lines,
  surfaces, and shapes.
• 4. Study one feature at a time and begin to put
  the shapes together to form the 3 dimensional
  shape of the object.

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Summary

• The purpose of an orthographic projection is to
  show an object in its true shape and size.
• The different views in an orthographic projection
  are projected at 90 degrees to each other.

12
Summary

• Four rules should be considered when selecting
  which views to use.
• Visualization involves being able to form a
  mental picture of what the object is to look
  like.
• Use the 4 visualization rules to help form a
  mental picture of the object.

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Summary Questions

• 1. What is an orthographic projection?
• 2. What are the proper locations of all six
  views that can be produced in an orthographic
  projection?
• 3. Out of the six possible views, why do we
  usually only select 3?
• 4. What 4 rules must you follow when selecting
  the views for an orthographic projection?
• 5. What is meant by visualization of an object?
• 6. What 4 rules are used in the visualization
  process?

14
Objectives

• Identify an orthographic projection.
• Select the best views to describe an object.
• Identify objects from an orthographic projection
  drawing.
• Identify the visualization rules of an
  orthographic projection drawing.

15
Assignment

• Identify the proper orthographic layout for the 3
  dimensional objects on page 45 in your book.
• Complete to an accuracy of 100.