NOCTI - National Occupational Competency Testing Institute Reading and Interpreting Blueprints Questions and Answers

Question 1

On an engineering drawing, what type of line is used to represent edges or features of an object that are not visible in the current view?

Accepted Answer

Hidden Line

Answer

Hidden lines, represented by a series of short dashes, are used to show surfaces, edges, or corners of an object that are concealed from the viewer in a particular orthographic projection.

Question 2

A machinist is preparing to manufacture a single component detailed on a blueprint. To verify the general dimensional tolerances that apply to all features unless otherwise specified, where is the FIRST place they should look?

Accepted Answer

Title Block

Answer

The title block of a drawing contains critical information for the entire sheet, which very often includes the default or general tolerance block that applies to all dimensions unless a specific tolerance is noted elsewhere.

Question 3

In a standard third-angle orthographic projection, which is common in the United States, if you are looking at the front view, how is the right-side view oriented?

Accepted Answer

To the right of the front view

Answer

In third-angle projection, views are placed on the side they are viewed from. Therefore, the right-side view is projected to the right of the front view, and the top view is projected above the front view.

Question 4

A feature on a drawing is specified with the symbol 'Ø'. What does this symbol indicate?

Accepted Answer

Diameter

Answer

The symbol 'Ø' is universally used on technical drawings to represent diameter. It precedes a numerical value to indicate the measurement across a circle passing through its center.

Question 5

A drawing is created with a scale of 2:1. A feature on the drawing measures 50mm. What is the actual size of the feature on the manufactured part?

Accepted Answer

25mm

Answer

A scale of 2:1 is an enlargement scale, meaning the drawing is twice the size of the actual part. To find the actual size, you must divide the measured dimension on the drawing by the first number in the scale ratio. Therefore, 50mm / 2 = 25mm.

NOCTI - National Occupational Competency Testing Institute Practice Test

NOCTI - National Occupational Competency Testing Institute Practice Test

NOCTI - National Occupational Competency Testing Institute Reading and Interpreting Blueprints Questions and Answers