Communicating design ideas using freehand sketching, 2D and 3D drawing such as isometric and perspective, working drawings, annotation, modelling and digital tools including CAD.

What this dot point is asking

This is AQA section 3.3.4. AQA wants you to know the range of ways designers communicate ideas, from quick freehand sketches to formal working drawings and CAD. You need to name the main drawing systems, explain the value of annotation and modelling, and describe what CAD offers. In Paper 1 this appears as questions on the difference between drawing systems, the purpose of a working drawing, and the advantages of CAD over hand methods.

Sketching and pictorial drawing

The right method depends on the audience and purpose. A designer sketches loosely to explore ideas, draws in isometric or perspective to present the look of a product to a client, and produces a precise working drawing to instruct a manufacturer. Oblique drawing (a flat front face with depth lines at 45 degrees) is a simpler 3D system sometimes used for quick studies. Adding rendering (shading, colour and texture) and tone makes a sketch read as a real material such as gloss plastic or brushed metal.

Working drawings and annotation

Orthographic drawings follow conventions (third-angle projection in the UK, a title block, dimension lines and a stated scale such as 1:2) so any manufacturer reads them the same way. Annotation turns a picture into a usable instruction: it records the material, size, finish, junction detail and reason for each feature, which is exactly what examiners look for when they ask you to develop an idea.

Modelling and CAD

• Physical models and mock-ups: rough versions in card, foam board or modelling foam test size, shape, ergonomics and function cheaply before committing to the final material. A toile does the same for a textile garment.
• CAD (computer-aided design): software produces accurate 2D and 3D models that are easy to edit, copy, scale, render photo-realistically and share by email or cloud. CAD models can be tested by simulation (for stress or fit), turned into exploded assembly views, and exported directly to CAM machines such as laser cutters and 3D printers, linking design straight to manufacture.

CAD has drawbacks too: software and hardware cost money, it needs training, and over-reliance can slow quick idea generation compared with a pencil. A strong answer weighs these against the benefits rather than treating CAD as always better.