GD&T Composite Feature Control 2

Question 1

In a composite feature control frame, the upper segment is called the:

Accepted Answer

Pattern-Locating Tolerance Zone Framework (PLTZF)

Answer

The upper segment of a composite feature control frame is called the Pattern-Locating Tolerance Zone Framework (PLTZF), which controls the location of the pattern as a whole.

Question 2

Which datum references are typically included in the Feature-Relating Tolerance Zone Framework (FRTZF) of a composite callout?

Accepted Answer

Only orientation datums, no location datums

Answer

The FRTZF typically references only orientation datums (like datum A for perpendicularity) but not location datums, since it controls feature-to-feature relationships rather than absolute location.

Question 3

A composite positional tolerance has PLTZF of ⌀0.8 and FRTZF of ⌀0.3. What does ⌀0.3 control?

Accepted Answer

The spacing between individual features within the pattern

Answer

The FRTZF tolerance of ⌀0.3 controls the spacing and orientation of features relative to each other within the pattern.

Question 4

Can a composite feature control frame be used with profile of a surface tolerances?

Accepted Answer

Yes, composite profile tolerances are explicitly defined in ASME Y14.5

Answer

ASME Y14.5 explicitly defines composite profile tolerances, where the upper segment controls location and the lower segment controls form, orientation, and feature-to-feature relationships.

Question 5

When a datum reference is repeated in both the PLTZF and FRTZF of a composite callout, what does it mean in the lower segment?

Accepted Answer

It restricts the FRTZF from translating relative to that datum

Answer

When a datum is repeated in the FRTZF, it restricts translation of the tolerance zone relative to that datum while still allowing the zone to shift in other directions.

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

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

GD&T Composite Feature Control 2