GD&T Tolerances & Fits in Engineering Drawings 5

Question 1

Which condition produces maximum clearance in a clearance fit?

Accepted Answer

Smallest shaft with largest hole

Answer

Maximum clearance occurs when the shaft is at its smallest (LMC) and the hole is at its largest (LMC), giving the most play.

Question 2

A drawing note states 'ALL TOLERANCES ±0.005 UNLESS OTHERWISE SPECIFIED.' A dimension shown as 3.750 +0.010/−0.000 would have which tolerance applied?

Accepted Answer

+0.010/−0.000 as shown on the dimension

Answer

A specific tolerance shown on a dimension always overrides the general title block tolerance for that particular feature.

Question 3

What is the purpose of using a running and sliding fit (RC fit) classification in ANSI B4.1?

Accepted Answer

To provide controlled clearance for parts that move relative to each other

Answer

RC (Running and Clearance) fits are designed to provide controlled clearance allowing relative motion between assembled parts.

Question 4

When converting between unilateral and bilateral tolerance expressions, a dimension of 25.00 +0.06/−0.00 is equivalent to:

Accepted Answer

25.03 ± 0.03

Answer

The midpoint is 25.00 + 0.03 = 25.03, and the equal bilateral deviation is ±0.03, giving 25.03 ± 0.03.

Question 5

In a virtual condition analysis, the virtual condition of an external feature (pin) at MMC with a straightness tolerance of 0.01 mm is:

Accepted Answer

MMC diameter plus the straightness tolerance

Answer

Virtual condition for an external feature = MMC size + applicable geometric tolerance, representing the worst-case boundary.

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

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

GD&T Tolerances & Fits in Engineering Drawings 5