Why do we prefer 1st and 3rd angle projection?

We consider that horizontal plane rotates in clockwise direction after having projection on it. that’s why we use 1st angle and 3rd angle projection. because only in this two quadrants we will get the both views after clockwise rotation of horizontal plane.

Does the world mostly use 1st or 3rd angle projection?

The two orthogonal projection methods used internationally are first angle projection and third angle projection. 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 drawings?

The difference between first and third angle projection is in the position of the plan, front and side views. In third angle, what you see from the right would be drawn on the right. In first angle, the view from the right would be projected through and drawn on the left.

What is 3rd angle projection used for?

3rd Angle project is where the 3D object is seen to be in the 3rd quadrant. It is positioned below and behind the viewing planes, the planes are transparent, and each view is pulled onto the plane closest to it. The front plane of projection is seen to be between the observer and the object.

Which angle projection is not recommended?

Therefore fourth angle projection is also not used. To sum up, Because of the overlapping of front and top views 2nd and 4th angle projections are not used. First and third angle projection systems are recommended for orthographic projections.

Why we do not use 2nd and 4th angle projection?

As per rule of projection when horizontal plane is rotated 90 degree in clockwise direction, top and front view will overlap. Overlapping projection views create confusion in the drawing. Therefore 2nd angle projection system is not used. Therefore fourth angle projection is also not used.

Who uses 1st angle projection?

First angle projection is widely used in India and European countries. The object is placed between the observer and projection planes. The plane of projection is taken solid in 1st angle projection.

What is third angle projection in engineering drawing?

Why 2nd and 3rd angle projection are not used?

As per rule of projection when horizontal plane is rotated 90 degree in clockwise direction, top and front view will overlap. Overlapping projection views create confusion in the drawing. Therefore 2nd angle projection system is not used.

Which of the following is correct sequence of views for 3rd angle of projection?

Explanation: In the third angle projection the top view of the object is above the front view and then come the side views to the left and right of front view and then back view which can either be kept on ends of side views but as standard notation it is placed on right side of right side view.

What is 3rd angle and 1st angle projection?

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.