Design Communication and Representation
Design communication is about choosing the right representation for the audience and purpose. Candidates must know the conventions of orthographic projection (third-angle versus first-angle, plan, elevation, end view), isometric and oblique pictorials, section views, exploded views, and detail drawings. Understand scale, dimensioning rules (dimensions outside the view, no repeated dimensions, units stated once), line conventions (visible, hidden, centre, construction), and title blocks.
Beyond technical drawing, know sketching, rendering, physical models, and digital models, and when each is most effective. A concept sketch communicates intent quickly; a dimensioned drawing communicates manufacture; a rendered model communicates appearance to a client. A common trap is mixing audiences - a client presentation rarely needs full dimensioning, while a fabricator needs it. Another trap is misreading a projection symbol or assuming a view is first-angle when the symbol shows third-angle.
Also revise digital communication: CAD file types, layering, and the value of parametric models that update when a dimension changes. Understand accessibility of communication - clear labels, consistent symbols, legible annotation.
Worked example / rule of thumb: Given a front view and a top view, produce the side view by projecting heights across and depths down, aligning features carefully. Rule of thumb: match the drawing to the reader - ask 'who uses this and what decision do they make with it?' If the answer is 'a manufacturer', dimension it; if 'a client', render it. In multiple-choice items, the correct option usually names both the representation and its purpose.