GD&T GD&T ASME Y14.5 Standards and Drawing Interpretation 2

Question 1

Reading a feature control frame left to right, what is the correct order of information?

Accepted Answer

Geometric characteristic symbol, tolerance value with any modifiers, datum references in precedence order

Answer

A feature control frame is read: (1) what is being controlled (symbol), (2) how much (tolerance + modifiers), (3) relative to what (datum references A, B, C).

Question 2

What does the circled M symbol (ⓜ) in a feature control frame indicate?

Accepted Answer

Maximum Material Condition — bonus tolerance applies as the feature departs from MMC

Answer

The encircled M specifies the MMC modifier, enabling bonus tolerance that grows as the actual feature size departs from its maximum material size.

Question 3

What is a basic dimension on an engineering drawing?

Accepted Answer

A theoretically exact value, shown in a rectangular box, used to define the perfect geometry from which GD&T tolerance zones are measured

Answer

Basic dimensions (shown boxed) are perfect, zero-tolerance values that locate or orient GD&T tolerance zones; all tolerance is captured in the feature control frame, not the dimension itself.

Question 4

What does a reference dimension (shown in parentheses) mean on a drawing?

Accepted Answer

It is provided for information only and is not used for inspection or part acceptance

Answer

Reference dimensions are informational, typically derived from other dimensions, and are never directly inspected or used to accept or reject a part.

Question 5

In a composite feature control frame with two segments, what does the upper segment control?

Accepted Answer

The location of the entire pattern relative to the datum reference frame

Answer

The upper segment of a composite callout controls where the pattern is located relative to the specified datums, while the lower segment refines the within-pattern accuracy.

(GD&T) Geometric Dimensioning and Tolerancing Certification Practice Test

(GD&T) Geometric Dimensioning and Tolerancing Certification Practice Test

GD&T GD&T ASME Y14.5 Standards and Drawing Interpretation 2