8 - Three-dimensional illustrations using isometric and oblique projection

Abstract

This chapter concentrates mainly on Isometric Projection. This type of view is commonly used in pictorial presentations, for example in car and motor-cycle service manuals and model kits, where an assembly has been ‘exploded’ to indicate the correct order and position of the component parts. With illustration and formulae, it describes the isometric scale to give the correct reduction in length for lines in an isometric view. Oblique Projection is covered with examples and tips on perfecting the projection. In both oblique and isometric projections, no allowance is made for perspective, and this tends to give a slightly unrealistic result, since parallel lines moving back from the plane of the paper do not converge. Reference to BS EN ISO 5456-3 is made for additional pictorial representations such as dimetric, trimetric, cavalier, cabinet, planometric, and perspective projections.