Difference between first and third angle projection in mechanical drawings.

Question

Accepted Answer

First angle projection and third angle projection are two different methods used in mechanical drawings 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 surrounding the object.
In third angle projection, the object is placed in the third quadrant and the views are projected onto the planes inside the object.
First angle projection uses a top view, front view, and right-side view, while third angle projection uses a top view, front view, and left-side view.
The symbol for first angle projection is a square with a dot inside, while the symbol for third angle projection is a square with a cross inside.

Accepted Answer

First angle projection is commonly used in Europe and Asia, while third angle projection is commonly used in North America

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