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What is first angle and third angle projection in engineering drawing?

What is first angle and third angle projection in engineering drawing?

To get the first angle projection, the object is placed in the first quadrant meaning it’s placed between the plane of projection and the observer. For the third angle projection, the object is placed below and behind the viewing planes meaning the plane of projection is between the observer and the object.

What is difference between 1st angle and 3rd angle projection?

The object is placed behind the vertical planes and bottom of the horizontal plane. Third angle projection is widely used in the United States….Difference between First Angle Projection and Third Angle Projection :

SR.NO First Angle Projection Third Angle Projection
3 The plane of projection is opaque. The plane of projection is transparent.

Who uses 1st and 3rd angle projection?

Orthographic Representation Third angle projection (figure 1.2) is used mainly in The United States and Canada whilst first angle projection (figure 1.1) is used mainly throughout Europe and the rest of the world.

What is the difference between first and third angle projection?

To get first angle projection object is place in between the plane of projection and observer and for the third angle projection plane of projection is placed between the object and observer. State of Projection Plane. In first angle of projection plane of projection is taken solid while in third angle of projection it is taken as transparent.

Which countries use third angle projection?

United States and Australia uses the Third Angle Projection method as their default projection system. The object is placed in the third quadrant for the third angle projection. Both are schemas used for multiview projection of three-dimensional objects using a series of two-dimensional drawings.

What is meant by first angle projection?

First Angle Projection is one of the ways of representing three-dimensional objects with respect to two dimensions which is commonly used in Europe and most of the world except the United States.

Why do we use third angle projection?

3rd angle projection is a type of orthogonal projection system where the object is placed in the third quadrant and the projection plane lies in between the observer and the object. Third angle projection system is widely used in United State and Asian countries. To draw front and top views in 3rd angle projection.