Final answer:
Auxiliary views are used when an object has a complex shape, needs to be represented in multiple dimensions, or is symmetrical and requires a 3D representation. They are not typically needed when an object is small and requires enlargement for clarity.
Step-by-step explanation:
When a drafter needs to draw auxiliary views of an object depends on the complexity of the object and the level of detail required. Auxiliary views are used to show additional features of an object that cannot be accurately represented in the other standard orthographic views. For example, if an object has a complex shape with curves or contoured surfaces, auxiliary views can be used to provide a more detailed illustration of those features.
Another circumstance in which auxiliary views may be needed is when the object needs to be represented in multiple dimensions. Standard orthographic views (top, front, side, etc.) only provide a two-dimensional representation of the object. Auxiliary views can be used to present additional dimensions, such as depth or height, in a more accurate and detailed manner.
Additionally, auxiliary views may be necessary when the object is symmetric and requires a three-dimensional representation. Symmetric objects may appear differently from different angles, and auxiliary views can help capture the object's complete shape and symmetry.
On the other hand, auxiliary views are not typically used when an object is small and requires enlargement for clarity. In such cases, other techniques like zooming in or scaling up the standard orthographic views are often sufficient to provide the necessary clarity.