GD&T concept check: which term describes the state in which a finished feature contains the maximum amount of material allowed by its size tolerance (for example, smallest hole or largest shaft)?

Difficulty: Easy

Correct Answer: Maximum material condition

Explanation:

Introduction / Context:Geometric tolerancing often references material condition modifiers to relate permissible geometric error to part size. Understanding these states is key for functional gaging and tolerance stack analysis.

Given Data / Assumptions:

  • A feature of size (hole or shaft) has stated limits.
  • We consider the condition with most material present.
  • Standard GD&T terminology is used.

Concept / Approach:Maximum Material Condition (MMC) is the size at which a feature contains the most material: for a shaft, the largest permissible diameter; for a hole, the smallest permissible diameter. It is commonly marked with the MMC symbol in feature control frames.

Step-by-Step Solution:

For shafts: more material → larger size within tolerance → MMC at upper limit.For holes: more material → smaller size within tolerance → MMC at lower limit.Therefore, the correct term is Maximum Material Condition.

Verification / Alternative check:Functional gages often simulate virtual condition boundaries based on MMC; parts that pass such gages will assemble in worst-case scenarios.

Why Other Options Are Wrong:

  • Machined material condition / Maximum machined indication / Machine mark indication: Nonstandard or incorrect terminology.

Common Pitfalls:Confusing MMC with Least Material Condition (LMC), which is the opposite (smallest shaft, largest hole).

Final Answer:Maximum material condition

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