# Technical Drawing CHAPTER 1

## Presentation on theme: "Technical Drawing CHAPTER 1"— Presentation transcript:

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?
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 Projection used mainly in USA
END VIEW FRONT VIEW ISOMETRIC PLAN

1st Angle Projection Symbol
FRONT VIEW SIDE VIEW SIDE VIEW FRONT VIEW

Used in UK and in most countries of the world
3rd Angle Projection Used in UK and in most countries of the world PLAN ISOMETRIC FRONT VIEW END VIEW

3rd angle Projection Symbol
FRONT VIEW SIDE 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

Correctly identify and draw different types of line.
MODULE OBJECTIVES 1.5 By the end of this module the student will be able to: Correctly identify and draw different types of line.