What is first angle and third angle projection?

Question

Accepted Answer

First angle and third angle projection are two methods used in engineering drawing to represent a 3D object on a 2D plane.

First angle projection is commonly used in Europe and Asia, while third angle projection is commonly used in North America.
In first angle projection, the object is placed in the first quadrant and the views are projected onto the planes behind the object.
In third angle projection, the object is placed in the third quadrant and the views are projected onto the planes in front of the object.
First angle projection is often represented by placing the front view above the top view, while third angle projection is represented by placing the front view below the top view.
Both methods follow specific conventions for representing different views of the object, such as top view, front view, and side views.

Accepted Answer

In first angle projection the top view is positioned below the front view with the left side view of the object to the right side of the front view.

In third angle projection the top view appears above the front view with right side of the object to the right of the front view

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