Which views are required to represent the true shape and length of inclined surfaces?

Auxiliary views are essential for accurately representing the true shape and length of inclined surfaces. These views are used in technical drawing and drafting to portray features that are not parallel or perpendicular to the principal planes of projection (front, top, or side views). An inclined surface, when viewed from the standard orthographic projections, can appear distorted, leading to a misrepresentation of its dimensions.

By utilizing auxiliary views, one can project the inclined surface onto a plane that is parallel to the surface being examined. This allows for a true representation of angles and elongations which can then be dimensioned accurately. It effectively eliminates the distortions created by the conventional viewing angles and provides a clearer picture of the object's geometry.

In contrast, perspective views create a sense of depth that can obscure true measurements, oblique views are useful for illustrating features but do not maintain true shape and scale, and detail views typically focus on showing a specific area with more clarity, which may not capture the inclined surfaces' true dimensions.