Difference between the First angle and Third angle projection

Orthographic Projection is a way of drawing an object from different directions. Usually a front, side and plan view are drawn so that a person looking at the drawing can see all the important sides. Orthographic drawings are useful especially when a design has been developed to a stage whereby it is almost ready to manufacture.

Both third angle and first angle projection display the standard three orthographic views of a part or assembly. The key difference between third angle and first angle is the layout of the part on the sheet.

Note: Changing the projection in the sheet properties will not update already inserted model views. Ensure that a drawing and or drawing package is in the standard projection format as mislabelling the drawing as third angle in the title block and putting the part in first angle can lead to a misunderstanding and or confusion on design intent.