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

Question

Accepted Answer

1st and 3rd angle projection are two different methods used in technical drawing to represent 3D objects on 2D surfaces.

1st angle projection is commonly used in Europe and Asia, while 3rd angle projection is commonly used in North America.
In 1st angle projection, the object is placed in the first quadrant and the views are projected onto the planes of projection.
In 3rd angle projection, the object is placed in the third quadrant and the views are projected away from the planes of projection.
The symbol used to indicate the type of projection is different for 1st and 3rd angle projection.
Understanding the difference between 1st and 3rd angle projection is important for accurately interpreting technical drawings.

Accepted Answer

Both are same, but the way of representation is different depending upon the relatives location of plane of projection and the object

In India first angle is preferred

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