Drafting & Design Principles & Techniques Flashcards
7 cards from real CDT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Drafting & Design Principles & Techniques flashcards as text
Which type of dimensioning places dimension strings from a single fixed baseline, eliminating the accumulation of tolerances?
Answer: Baseline (datum) dimensioning
Baseline dimensioning measures each feature independently from a common datum, so individual tolerances do not stack up.
In an isometric drawing, circles appear as:
Answer: Ellipses oriented along the isometric axes
Because isometric axes are drawn at 30° from horizontal, circles on isometric planes project as ellipses with their major axes aligned to the isometric axis.
The 'glass box' concept in orthographic projection means:
Answer: Imagining the object inside a transparent box and unfolding the box faces to create views
The glass box model helps students visualize how six orthographic views are obtained by projecting the object onto the faces of a transparent box that is then unfolded.
What is the difference between a 'limit dimension' and a 'plus/minus tolerance'?
Answer: Limit dimensions state the maximum and minimum allowable values directly, while plus/minus shows deviation from a nominal value
Limit dimensions explicitly give the upper and lower boundary values (e.g., 2.005/1.995), while plus/minus notation gives a nominal size with allowed deviation (e.g., 2.000 ±0.005).
When drawing a tangent line from an external point to a circle, how many such tangent lines can be drawn?
Answer: Exactly two
From any external point, exactly two tangent lines can be drawn to a given circle, each touching the circle at a unique tangent point.
In descriptive geometry, the 'edge view' of a plane is obtained when:
Answer: The line of sight is parallel to the plane, making it appear as a straight line
A plane appears as an edge (a single straight line) in any view where the line of sight is parallel to that plane.
Which ANSI line weight (thickness) is typically used for visible object lines in technical drawings?
Answer: Thick (0.5–0.7 mm)
Visible object lines are drawn with a thick line weight (approximately 0.5–0.7 mm) to stand out clearly from thinner lines such as dimensions and center lines.