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Technical Drawing CHAPTER 1. By : Aznita Abdullah. Why engineers use orthographic projection?. Engineers need to be able to explain and simplify complicated design ideas for others to understand. Why engineers use orthographic projection ?.
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Technical DrawingCHAPTER 1 By: Aznita Abdullah
Why engineers use orthographic projection? Engineers need to be able to explain and simplify complicated design ideas for others to understand.
Why engineers use orthographic projection? To show complicated 3 dimensional (3D) object in two dimension (2D)
ORTHOGRAPHIC PROJECTION • the object is looked at from three views at 90 degrees to each other.
ORTHOGRAPHIC PROJECTION – 3 VIEWS • Plan • Front View • Side View (or End View)
ORTHOGRAPHIC PROJECTION Viewed in 2 ways: • 1st Angle Projection • 3rd Angle Projection.
1st Angle Projectionused mainly in USA FRONT VIEW END VIEW ISOMETRIC PLAN
1st Angle Projection Symbol FRONT VIEW SIDE VIEW SIDE VIEW FRONT VIEW
3rd Angle Projection Used in UK and in most countries of the world ISOMETRIC PLAN FRONT VIEW END VIEW
3rd angle Projection Symbol SIDE VIEW FRONT VIEW FRONT VIEW SIDE VIEW
DIFFERENCE BETWEEN 1ST ANGLE AND 3RD ANGLE 1st Angle Projection 3rd Angle Projection
MODULE OBJECTIVES By the end of this module the student will be able to: 1.1 Describe orthographic projection 1.2 State why engineers use orthographic projection 1.3 Compare 1st degree angle and 3rd degree angle
MODULE OBJECTIVES 1.4 By the end of this module the student will be able to: Correctly sketch two-dimensional views from three dimensional drawings.
PLAN VIEW END VIEW FRONT VIEW
MODULE OBJECTIVES 1.5 By the end of this module the student will be able to: Correctly identify and draw different types of line.