Deck 17: Perpendicularity Tolerance

Question 1

What are the four shortcomings of implied 90-degree angles?

Answer 1

The general note for implied 90-degree angles may work for some drawings, but it does have four shortcomings:
1. The tolerance zone is wedge-shaped. It increases as the surface gets farther from the origin.
2. There is no datum sequence specified, which means there are at least two ways the part can be measured.
3. The lack of a specified dimension results in the requirement often being overlooked.
4. When general angular tolerances are inspected, common inspection methods often do not comply with the requirement for an angular dimension in the standard.

Question 2

In certain applications, part function requires the perpendicularity deviation of a surface to be defined relative to a(n) ____________________.

Answer 2

datum

Question 3

When a perpendicularity tolerance is applied to a planar surface, the deviation is verified by finding the distance between two parallel planes that all of the points of the surface are located within.

Answer 3

True

Question 4

A general angular tolerance or an angular dimension invokes a(n) ____________________-shaped tolerance zone.

Question 5

Where two datum references are used with a perpendicularity tolerance, the tolerance zone is perpendicular to the primary datum reference.

Question 6

A perpendicularity tolerance can only constrain rotational degrees of freedom relative to the datum referenced.

Question 7

____________________ is the condition where a surface, axis, or center plane is exactly 90 degrees to a datum plane or axis.

Question 8

Where perpendicularity is applied to a planar surface, what are the four conditions that apply?

Question 9

Perpendicularity can be applied to a planar surface, but not to a feature of size.

Question 10

Where a perpendicularity tolerance is applied to a width, the feature control frame is placed ____________________ (or beside) the size dimension.

Question 11

Where perpendicularity is applied to a width at RFS, the tolerance value defines the ____________________ between the tolerance zone planes.

Question 12

A common method used to verify a perpendicularity tolerance (MMC) is to use a height gage.

Question 13

Define a precision square and briefly explain how it is used.

Question 14

What are the two common tolerance zones for a perpendicularity tolerance?

Question 15

What are the four common real-world applications of a perpendicularity tolerance on a drawing?