Orthographic Projection 2 Dimensional View of an object

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Orthographic Projection2 Dimensional View of an
object
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ME20/Tech20 Engineering Design Graphics

• Graphics Theory

Geometry and projection techniques.
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Different Viewpoint
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Parallel Projection
Perspective
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Orthographic Projection
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Standard 2D views
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Standard Views of Primitive Solids
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View Orientation
Poor orientation
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View Selection
Use minimum number of views to describe the object
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Conventional PracticesHoles, Ribs Webs
Principle of Revolution
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Conventional Practices
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Conventional Practices - Intersections

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Miter Lines
Miter lines are used to transfer depth
information.
Standard multiviews
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Homework 1 Due Friday 9/8multiviews
Problems 6, 26, 47, and 57 page 276-280 (5th
edition) page 269-272 (4th edition) page
364 (3rd edition) Freehand sketch the three
standard views (front, top, and right side).
Select the left side of the 3D drawing as the
front view. Sketch 2 problems per page. Drawings
should be somewhat proportional.
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Conventional Practices - Tangency
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Fillets, Rounds Chamfers
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Top view
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(No Transcript)
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Edge Lines Principal Inclined
Principal lines appear vertical, horizontal or as
point views. Inclined lines appear inclined in
one view.
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Edge Lines Oblique
Oblique line appears inclined in all views
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Principal Planes
Principle planes are parallel to principal
orthographic planes
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Inclined Planes
Inclined planes are perpendicular to two opposite
orthographic planes.
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Oblique Planes
Oblique planes are neither parallel nor
perpendicular to any principal orthographic
planes.
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Type of Planes
Oblique
Inclined
Principal
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Edge View of a Plane
Principal planes appear in true size in one plane
and as an edge view in the other two planes.
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Homework 2 Due Friday 9/22/06
Pictorials
4th edition page 369-374, 5th edition page
376-381 freehand sketches, two drawings per page
1) Figure 7.61 draw a perspective view, choose
a vanishing point at the upper right hand corner
2) Problem 14 draw an oblique view.
3) Problems 4, 22, and 27 draw an isometric
view, looking down, the left ,
side of the isometric should be the front view.