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The distinguishing feature of axonometric projection, as

compared to multi view projection, is the inclined position of

the object with respect to the plane of projection. Since the

principal edges and surfaces of the object are inclined to the

plane of projection, the lengths of the lines, the sizes of the

angle, and the general proportions of the object vary with the

infinite number of possible positions in which the object may

be placed with respect to the plane of projection. Three of

these are shown below.

In these cases the edges of the cube are inclined to the plane

of projection, and therefore foreshortened. The degree of

foreshortening of any line depends on its angle with the plane

of projection; the greater the angle the greater the

foreshortening. If the degree of the foreshortening is

determined for each of the three edges of the cube which

meet at one corner, scales can be easily constructed for

measuring along these edges or any other edges parallel to

them. It is customary to consider the three edges of the cube

which meet at the corner nearest to the observer as the

axonometric axes.

Axonometric projections are classified as

a) Isometric projection

b) Dimetric Projection

c) Trimetric Projection, depending up on the number of

scales of reduction required.

lecnote_fm_engineering drawingTIOc and BodyEngineering Drawing.pdf