First Angle Projection vs Third Angle Projection

First Angle Projection vs Third Angle Projection:

First angle projection and Third angle projection are two different methods of creating a 2D drawing of a 3D part.

First Angle Projection is commonly used in all countries other than United States. It is mainly used in Europe and Asia countries. The Indian Standard Institution (ISI) recommend the use of First Angle Projection method now in all the institutions.

Third Angle Projection is commonly used in United States of America.

Following table describes what is the difference between or comparison between First Angle Projection vs Third Angle projection

Following are the details description of first angle projection vs third angle projection given in text note from above table for better readability.

First Angle Projection:

1. The object is imagined to be in first quadrant.
2. The object is lies between the observer and plane of projection.
3. The plane of projection is assumed to be non transparent.
4. When view are drawn in their relative position Top view comes below Front view, Right side view drawn to the left side of elevation.
5. A First Angle Projection drawing is identified by the first angle projection symbol. The angle of projection symbol typically appears in angle of projection block near to Title block.

Third Angle Projection:

1. The object is imagined to be in third quadrant.
2. The plane of projection lies between the observer and object.
3. The plane of projection is assumed to be transparent.
4. When view are drawn in their relative position Top view comes above Front view, Right side view drawn to the light side of elevation.
5. A Third Angle Projection drawing is identified by the third angle projection symbol. The angle of projection symbol typically appears in angle of projection block near to Title block.

Also Read Mechanical Engineering Basics

Important Notice: No part of www.enggwave.com or any of its contents may be reproduced, copied, modified or adapted, without the prior written consent of the author, unless otherwise indicated for stand-alone materials.