Auxiliary view taxonomy: which type of auxiliary view is projected onto a plane that is perpendicular to one principal projection plane in order to show true size of an inclined feature?

Introduction / Context:
Auxiliary views are categorized by how many times you depart from the principal planes. The most basic is the primary auxiliary, used to show a single inclined surface in true size by projecting onto a plane perpendicular to one principal plane.

Given Data / Assumptions:

• An object face is inclined to a principal plane (front, top, or right).
• We want a single-step projection to reveal true size.
• Terminology follows standard drafting texts (primary versus secondary auxiliary).

Concept / Approach:
A primary auxiliary view is obtained by projecting from a principal view onto an auxiliary plane set perpendicular to that principal plane and parallel to the inclined surface. A secondary auxiliary view would project again from the primary auxiliary when a feature is oblique to all principal planes.

Step-by-Step Solution:

Verification / Alternative check:
Measure an edge in the primary auxiliary and compare with model true length; they should match.

Why Other Options Are Wrong:

• Secondary: Requires two successive auxiliary projections; unnecessary here.
• Revolved: Used for showing cross-sections rotated in place along an axis.
• Successive: Not a standard term (secondary is).

Common Pitfalls:
Accidentally aligning the auxiliary plane incorrectly, leading to residual foreshortening.

Final Answer:
Primary