GD&T Symbols and Rules 3

Question 1

What does the 'free state' symbol (circle with the letter F) indicate in a GD&T callout?

Accepted Answer

The tolerance applies after release from manufacturing fixturing

Answer

The free state modifier indicates that the geometric tolerance applies to the part in its unconstrained, free state — not held in a fixture.

Question 2

A profile of a line tolerance differs from a profile of a surface tolerance in that it:

Accepted Answer

Controls only a cross-sectional slice at any given location

Answer

Profile of a line controls the shape of a cross-sectional profile at individual cross-sections, while profile of a surface controls the complete 3D form.

Question 3

In a feature control frame, the compartment immediately following the tolerance value compartment contains:

Accepted Answer

The primary datum reference

Answer

After the tolerance value (and any modifier on it), the next compartments list datum references in order: primary, secondary, then tertiary.

Question 4

Which symbol, when placed below a feature control frame, indicates that the tolerance applies to the entire length or surface — not per unit?

Accepted Answer

No additional symbol is needed; it applies to the entire extent by default

Answer

By default, a geometric tolerance applies to the full extent of the feature unless a 'per unit' basis is specified separately below the frame.

Question 5

Which of the following is NOT a valid runout tolerance symbol in ASME Y14.5?

Accepted Answer

Total Runout of a Plane Surface

Answer

There is no separate GD&T symbol called 'Total Runout of a Plane Surface'; Total Runout (the arrow symbol) covers cylindrical and planar surfaces within one symbol.

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

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

GD&T Symbols and Rules 3