What is the purpose of auxiliary views in engineering drawings?

Auxiliary views are specifically used in engineering drawings to depict features that are not readily visible or are difficult to represent in the standard front, top, and side views. When a part contains angles or inclined surfaces, these features can be obscured in the principal views, leading to confusion or misinterpretation. An auxiliary view is projected from one of the primary views at an angle that allows the engineer or designer to see these features in true size and shape, thereby providing clarity and improving the understanding of the object's geometry.

This helps in manufacturing and quality assurance, as the correct interpretation of all geometric details is critical to ensure that parts fit together as intended. In essence, auxiliary views function to illustrate internal or complex features clearly without the distortion that can occur in standard views, making them essential for effective communication in engineering drawings.