PICTORIAL Sketching /

ISOMETRIC SketchingBY SAFIULLAH 13CE07 SCET WAH CANTTCONTT;03479164097

Introduction

Orthographic view shows only two dimensions in

any particular view. This makes it difficult to

interpret them and only technically trained person

can interpret the meaning of these orthographic

views. A non-technical person Can not imagine the

shape of the object from orthographic projections.

Whereas, pictorial projections can be easily

understood even by persons Without any technical

training because such views show all the three

Dimensions Of an object in the same view.

But pictorial view does not show the true shape

and size of any principal surface of An object and

it does not show the hidden portions.

Pictorial projections are easy to imagine so these

are used in sales literature.

Principle of Projection :

If straight lines are drawn from various

points of an object to meet a plane then it

is said that object is Projected on that

plane.

These straight lines from the object to

the plane are called projectors.

The figure formed by joining the points at

which the projectors meet the plane is

called Projection of that object.

Types of Projection:I) Orthographic ProjectionII) Pictorial Projection

Pictorial Projection :The projection in which the length , height And depth are shown in one view iscalled Pictorial Projection.

Isometric Sketching / Isometric Projection :

An isometric sketch, although a pictorial or three

Dimensional drawing, is not drawn as an object

appears to the eye. It is made according to the

actual dimensions as for as possible. For this

reason it often looks unnatural. However, because

It can be dimensioned and it is easy to draw, an

Isomeric sketch is preferred in engineering works.

The projection is obtained on a plane which is

equally inclined to all the three principal planes.

When a cube is kept in particular position then it

gives isometric axes, isometric lines and isometric

planes.

Particular position : When cube is resting on H.P.

on corner G and diagonal EC is Perpendicular to

V.P. A

C

D

G

H

30o30o

Base LineM N

B

F

E

Isometric Axes :

The three lines CB,CD and CG meeting at the point

C and making angle of 120 degree with each other

are called isometric axes.

Isometric lines:

The lines parallel to isometric axes are called

isometric lines.

Isometric planes:

The planes represented by faces of cube are called

isometric planes.

Similarly any planes parallel to these planes are also

called isometric planes.

Isometric drawing or isometric view:

The pictorial view drawn with true scale is called

Isometric drawing or isometric view.

Isometric projection:

The pictorial view drawn with the use of isometric

scale is called Isometric projection.

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ISOMETRIC VIEW

NOTE:- IN R.H.S.MISSED VIEW, THE AREAS, A & B ARE SEEN AND IS DRAWN IN ITS CORROSPONDING SPACE

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