308A Blueprint Reading for Sheet Metal

Question 1

What do hidden lines (dashed lines) represent on a sheet metal blueprint?

Accepted Answer

Edges, surfaces, or features that are not visible from the current viewing angle

Answer

Cutting lines

Answer

Dimension lines

Answer

Centerlines

Question 2

What does a centerline (long dash-short dash pattern) indicate on a duct drawing?

Accepted Answer

The axis of symmetry, center of a round duct, or center of a feature like a hole

Answer

The cutting line for the pattern

Answer

The maximum dimension

Answer

The welding location

Question 3

What information is found in the title block of a sheet metal drawing?

Accepted Answer

Project name, drawing number, scale, material, gauge, date, revision, and the drafter's name

Answer

Only the drawing number

Answer

Only the material type

Answer

Only the customer's name

Question 4

What does a scale of 1/4" = 1'-0" mean on a sheet metal drawing?

Accepted Answer

Every 1/4 inch on the drawing represents 1 foot in actual size

Answer

The drawing is full size

Answer

The metal is 1/4 inch thick

Answer

The drawing is 4 times larger than actual size

Question 5

What do section lines (hatching) indicate on a sheet metal drawing?

Accepted Answer

Cut surfaces exposed by an imaginary cutting plane through the object

Answer

Areas to be painted

Answer

Areas of insulation

Answer

Ventilation openings

Question 6

What is the purpose of a 'detail drawing' in a set of sheet metal construction documents?

Accepted Answer

To show an enlarged view of a specific area, connection, or fitting with complete fabrication dimensions

Answer

To show the overall building layout

Answer

To list all materials needed

Answer

To show the electrical layout