Applied Graphics
Applied Graphics
Applied Graphics tests whether you can turn a real object or brief into clear technical drawings and read drawings back into 3D form. Expect orthographic projection, scales, dimensioning, line conventions, sectional and auxiliary views, and freehand or CAD presentation.
Core rules
- Use first-angle orthographic projection unless the paper states otherwise: the view from the front is placed above the plan, and the view from the left is placed on the right.
- Match line types to purpose: continuous thick for visible outlines, continuous thin for dimension, extension and construction lines, dashed for hidden edges, and chain thin for centre lines.
- Dimension once only, on the view that shows the feature most clearly; avoid dimensioning hidden lines. Give overall sizes plus locating dimensions.
- Scale drawings: drawn length = real length × scale factor. A 1:2 scale halves every length; a 1:50 scale divides by 50. State the scale on the sheet.
Worked example
A bracket is 120 mm long, 80 mm high and 30 mm deep. Draw its front elevation at 1:4. Scale factor = 1/4, so drawn length = 120/4 = 30 mm and drawn height = 80/4 = 20 mm. The depth is not shown in the front elevation; it belongs in the plan or end view. Mark the scale as 1:4 under the drawing. If the drawing were enlarged at 2:1, each real millimetre would become two drawn millimetres.
Traps
Mixing first- and third-angle placement; using hidden lines where visible outlines are needed; double-dimensioning; forgetting units or the scale; drawing dimension text upside down; and letting construction lines remain as heavy outlines.