CDT Structural & Mechanical Drafting Flashcards

In mechanical drafting, what does the term 'scale 1:2' on a drawing mean?

Answer: The drawing is half the size of the actual part

A scale of 1:2 means one unit on the drawing equals two units on the actual part, so the drawing is drawn at half size.

What is the purpose of a machining finish symbol (surface texture symbol) on a US engineering drawing?

Answer: To specify the required surface roughness or finish quality of a machined surface

Surface texture symbols specify the required Ra (average roughness) or other finish parameters that the machined surface must meet after processing.

Which structural member is typically used in US steel construction to resist bending loads in horizontal beams?

Answer: Wide-flange (W-shape) beam

Wide-flange (W-shape) beams are the most common steel structural members used as horizontal beams because their geometry efficiently resists bending through flange area at the top and bottom.

In mechanical drafting, what does the abbreviation 'FAO' mean?

Answer: Finish All Over — all surfaces must be machined

FAO stands for 'Finish All Over,' meaning every surface of the part must be machined to the specified finish.

When a structural connection uses a gusset plate, its primary function is to:

Answer: Distribute and transfer loads between structural members at a joint

A gusset plate is a flat steel plate used to connect and transfer forces between structural members, particularly at truss joints and frame connections.

What is the standard US paper size used for large-format engineering drawings?

Answer: D-size (22 × 34 in)

D-size (22 × 34 inches) is a standard ANSI large-format engineering drawing sheet commonly used for detailed structural and mechanical drawings.