Difference between First & Third Angle

Question

Accepted Answer

First and Third Angle are two different methods of representing orthographic projections in engineering drawings.

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 is considered more intuitive as it mimics the way we naturally view objects, while Third Angle Projection is more common in engineering practice.
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.

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