Difficulty: Easy
Correct Answer: Incorrect
Explanation:
Introduction / Context:
Drawings frequently show features at right angles without explicitly writing “90°.” These are implied right angles. The question is whether such implied angles usually receive distinct, special general tolerances compared to other angles in the same drawing.
Given Data / Assumptions:
Concept / Approach:
By default, the drawing’s general angular tolerance applies to all angles not otherwise controlled. If tighter control is needed at 90°, designers apply GD&T (e.g., perpendicularity relative to a datum) or write a local note. Without such a note, an implied 90° is treated like other angular dimensions for general tolerance purposes.
Step-by-Step Solution:
Check the general tolerance note: one angular tolerance typically covers all unstated angles.Determine whether a special callout exists for the implied 90°.If none, it shares the same general tolerance as other angles.Thus the claim that implied 90° “typically” have different general tolerances is incorrect.
Verification / Alternative check:
Inspect sample title blocks: angular tolerances are global unless overridden; implied right angles are not singled out by default.
Why Other Options Are Wrong:
“Correct” contradicts common practice. Conditions about datums, projection method, or material category do not inherently change the general tolerance assignment.
Common Pitfalls:
Confusing GD&T perpendicularity control with a global special angular tolerance; assuming implied 90° always requires a unique limit.
Final Answer:
Incorrect
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