Orthographic projections are used to create 2D technical drawings of 3D objects by drawing views as they would be seen from the front, top, and sides. These views are drawn by observing a pictorial view of the object. Multi-view drawings provide an accurate representation of objects and structures using orthographic projections and are important for engineering, manufacturing, and construction. There are two main systems for orthographic projections: first angle and third angle.

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2. Orthographic projections
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I n orthographic projections, the principle views –
Front view, Top view, & Side views of an object are
drawn by the direct observation.
These views are drawn from the pictorial view of
an object. The pictorial view is a three dimensional
representation.
B y observing pictorial view, it is very easy to visualize
the shape when the object is viewed from front, top &
sides.

3. Orthographic Projection
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Multi-view drawings provide the most accurate
description of 3D objects and structures for engineering,
manufacturing, and construction requirements
In engineering, there are two systems of projection:
F i r s t Angle Projection – Europe, Asia and former
European colonies in Africa and parts of Australia
T h i r d Angle Projection – Used in the USA and
Canada, in Africa where American development is
taking place and parts of Australia

4. ConventionalProjectio ns
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5. `
ORTHOGRAPHIC PROJECTIONS
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6. Orthographic projections
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7. Views What Seen
Front view Length and Height–(width not consider)
Top view
Side view
Length and width–(Height not consider)
Height and width–(Length not consider)
Arrangement of views
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8. Representation of orthographic views
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9. Representation of ortho graph ic views
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10. Representation of ortho
graph
ic views
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11. Representation of ortho
graph
ic views
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12. Representation of ortho
graph
ic views
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13. Representation of ortho
graph
ic views
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14. Representation of ortho
graph
ic views
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15. Representation of ortho
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ic views
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16. Representation of ortho
graph
ic views
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17. Representation of ortho
graph
ic views
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18. Representation of ortho
graph
ic views
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19. Representation of ortho
graph
ic views
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20. Representation of ortho
graph
ic views
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21. Representation of orthographic views
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22. Representation of ortho
graph
ic views
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23. Representation of ortho
graph
ic views
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24. Representation of ortho
graph
ic views
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25. Representation of ortho
graph
ic views
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26. Representation of ortho
graph
ic views
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27. Representation of ortho
graph
ic views
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28. Representation of ortho
graph
ic views
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