Technical Drawing Flashcards
7 cards from real AIT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Technical Drawing flashcards as text
What is the purpose of a 'break' symbol on a long uniform part in a technical drawing?
Answer: To shorten the drawing representation without changing the stated length dimension
Break lines allow a long, uniform object to be drawn at a larger, clearer scale while the true overall length is still specified in the dimension.
In the Unified thread system, what does the designation 'UNF' indicate compared to 'UNC'?
Answer: UNF has more threads per inch (fine pitch); UNC has fewer threads per inch (coarse pitch)
Unified National Fine (UNF) threads have a smaller pitch and more threads per inch than Unified National Coarse (UNC), providing greater holding strength in thin materials.
A 'spotface' operation is called out on a drawing when:
Answer: A small flat bearing area must be machined around a hole on a rough or curved surface
Spotfacing machines a shallow, flat circular area around a hole so a bolt head or washer seats squarely on an otherwise rough or angled surface.
What does the abbreviation 'TYP' mean when placed next to a dimension on a drawing?
Answer: The same dimension applies to all identical features unless noted otherwise
'TYP' (typical) indicates that the dimension or note applies to every similar feature on the drawing without having to dimension each one individually.
Which view is added to a multiview drawing when a surface is not parallel to any principal projection plane?
Answer: An auxiliary view
An auxiliary view is projected perpendicular to the inclined surface so its true shape and size are shown without distortion.
When a drawing callout reads 'Ø.375 ±.005 THRU', what does 'THRU' specify?
Answer: The hole goes completely through the part from one side to the other
'THRU' (or 'THROUGH') indicates the hole passes entirely through the part, eliminating any ambiguity about depth.
In a surface finish callout, what does the Ra value represent?
Answer: The arithmetic average roughness of the surface measured from the mean line
Ra is the arithmetic mean of the absolute deviations of the surface profile from the mean line, expressed in microinches or micrometers.