GD&T - Geometric Dimensioning and Tolerancing Material Condition Modifiers Questions and Answers

Question 1

Which of the following applications is the primary reason for specifying a geometric tolerance at Least Material Condition (LMC)?

Accepted Answer

To guarantee a minimum wall thickness is maintained between two features.

Answer

To ensure the assembly of a pin into a hole.

Answer

To control the form of a feature independently of its size.

Answer

To simplify inspection by allowing the use of a single functional gage.

Question 2

A feature control frame for a positional tolerance specifies Ø0.2 mm. No material condition modifier symbol is present. The controlled feature is a hole with a size of 15.0 ±0.3 mm. If an inspector measures the actual size of the hole to be 15.2 mm, what is the total permissible positional tolerance?

Accepted Answer

Ø0.2 mm

Answer

Ø0.4 mm

Answer

Ø0.1 mm

Answer

Ø0.3 mm

Question 3

An external feature (a pin) is specified as Ø8.0 ±0.2 mm. A perpendicularity tolerance of Ø0.1 mm is applied at Least Material Condition (LMC). If the pin is produced at its largest size (Ø8.2 mm), what is the total allowable perpendicularity tolerance?

Accepted Answer

Ø0.5 mm

Answer

Ø0.1 mm

Answer

Ø0.3 mm

Answer

Ø0.4 mm

Question 4

What is the primary advantage of specifying a geometric tolerance of zero at Maximum Material Condition (e.g., ⌖|Ø0Ⓜ|A|B|C|)?

Accepted Answer

It forces the tolerance to be entirely dependent on the feature's departure from its MMC size.

Answer

It eliminates the need for datum features in the callout.

Answer

It requires all produced parts to have perfect form at MMC.

Answer

It mandates that the feature must be produced exactly at its LMC size.

Question 5

A material condition modifier (MMC or LMC) can be applied in the feature control frame for which of the following geometric tolerances?

Accepted Answer

Perpendicularity

Answer

Flatness

Answer

Circularity

Answer

Cylindricity

Question 6

What is the correct definition of Virtual Condition for an INTERNAL feature of size (e.g., a hole) when a geometric tolerance is applied at Maximum Material Condition (MMC)?

Accepted Answer

The MMC size of the feature minus the stated geometric tolerance.

Answer

The LMC size of the feature plus the stated geometric tolerance.

Answer

The MMC size of the feature plus the stated geometric tolerance.

Answer

The LMC size of the feature minus the stated geometric tolerance.