Principal Planes and Parallel to the Other Principal Plane:
While the axis of a solid is inclined to any principal plane, the final projections are received in two stages. Here in first stage, the axis of the solid is assumed to be perpendicular to the principal plane, to that it is actually inclined and the views are drawn. The final projections may be obtained via one of as given two methods and they are:
(a) Alteration of position or location method.
(b) And Alteration of reference line.
During method (a), the position of one of the view is altered to suit the specified condition and the other view is projected from it.
During method (b), instead of reconstructing one of the views as mentioned above, an auxiliary plane is imagined; satisfying the specified condition and the other view is projected on it. It is advantageous compared to method (a) like this avoids redrawing of one of the views, especially whenever the solid has curved surfaces or many more corners and edges.