Engineering Graphics–Projection of Planes

PROJECTION OF PLANES

A Plane is a two dimensional entity having only length and breadth with negligible thickness which is considered as zero.

TYPES OF PLANES

Planes may be divided as two main types. They are

(I) Perpendicular Planes

(II) Oblique Planes.

Perpendicular Planes

Planes which are perpendicular to any one of the principal planes of projection are called as perpendicular planes. These planes may be inclined or parallel to the other principal plane.

Various positions of perpendicular planes

(a) Planes perpendicular to V.P. And Parallel to H.P.

Consider a plane perpendicular to V.P. And Parallel to H.P. The top view reveals the true shape of the plane

The front view is a line parallel to xy line.

(b) Planes perpendicular to H.P. And Parallel to V.P.

Consider a plane perpendicular to H.P. And Parallel to V.P. The front view shows the exact shape and size of the plane. The top view is a line parallel to xy line

© Plane perpendicular to both H.P. And V.P.

Consider a plane in space which is perpendicular to both the H.P & V.P.

Both the front view and top view of the plane appear as a straight lines on a single projector.

(d) Plane perpendicular to V.P. And inclined to H.P.

Consider a plane perpendicular to V.P. And inclined at an angle to the H.P. The top view is shorter than its ture size.

The front view is a line inclined at an angle to xy line .

(e) Plane perpendicular to H.P. And inclined to V.P.

Consider a plane perpendicular to the H.P. And inclined at an angle to the V.P. The front view is shorter than its true size.

The top view is a line inclined at an angle to xy line.