Isometric ProjectionsIsometric ProjectionsDeveloped By:Prajapati Yash

AHMEDABAD INSTITUTE OF TCHNOLOGY

Guided By:Prof.

IntroductionOrthographic 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.

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.

F.V.

T.V.

L.H.S.V.

X

Aim:- Figure-1, shows the F.V. & T.V. of a simple vertical rectangular plane of size LH. Draw its isometric view, for (a) R.H.S.V. & (b) L.H.S.V.

c’

b’a’

d’ L

H

F.V.a

T.V.Figure-1

bcd

A

B

C

D

Figure-1(a)X

P

Q

R

M N

L H

MN, is the base line for isometric axes.

PQ, is the isometric axis (vertical) for Fig.1(a)

PR, is the isometric axis ( horizontal),for R.H.S.V. for Fig.1(a) at 30º with base line MN.

Note:-Note:- The diagonal line The diagonal line a’c’ in ortho. View a’c’ in ortho. View increases in its iso. View increases in its iso. View (Fig.1-a), as AC (known (Fig.1-a), as AC (known as, non isometric line)as, non isometric line)

MN, is the base line for isometric axes.

PQ, is the isometric axis (vertical) for Fig.1(b)

P

Q

M ND

A

B

C

Figure-1(b)X

S

LH

PS, is the isometric axis ( horizontal),for L.H.S.V. for Fig.1(b) at 30º with base line MN.

Note:-Note:- The diagonal line The diagonal line a’c’ in ortho. View a’c’ in ortho. View decreases in its iso. View decreases in its iso. View (Fig. 1-b), as AC (known (Fig. 1-b), as AC (known as, non isometric line) as, non isometric line)

d c

ba

Figure shows the Top View of a rectangular plane of 100 x 70. Draw its isometric view i) for R.H.S.V & ii) for L.H.S.V.

100

70

T.V.

A

DB

CX

10070

ISOMETRIC VIEW OF THE HORIZONTAL RECTANGULAR PLANE (100 X 70) for its R.H.S.V.

30 30

B

C

D

A

ISOMETRIC VIEW OF THE HORIZONTAL RECTANGULAR PLANE (100 X 70) for its L.H.S.V.

X

100

70

3030

Aim:-Figure shows the T.V. of a cut geometric plane. Draw its Isometric, (i)For R.H.S.V.

& (ii) For L.H.S.V.?

hkL1a

b c ed

f

g

ij

L

D

L2

45 45D1

T.V.

30

R

ED=EF=RED=EF=RBC=bc= ?BC=bc= ?AK=ak=L1 GH=gh=L2

Draw, J I // AG ( at a distance of D1 )Note :- (1) MJ=KM=D1, as

angle jka=45 (2) Angle JKA &

Angle IHG are not 45 in isometric.

hkL1a

b c ed

f

g

ij

L

D

L2

45 45D1

T.V.

30

?

R

30(i)

L2

H

A L1 D 1

45

D?

L45

30

R

B

CD

E

F

G

I

J

K

M

N

X

hkL1a

b c ed

f

g

ij

L

D

L2

45 45D1

T.V.

30

?

R

Note :- (1) MJ=KM=D1, as angle jka=45

(2) Angle JKA & Angle IHG are not 45 in isometric.

BC=bc= ?BC=bc= ?AK=ak=L1

Draw, J I // AG ( at a distance of D1 )

DD

1H

J

(ii)30

45

45

L 1

?L 2

30

R

XA

B

CD

EF

GI

K

N

M L

aabb

cc

ddee

gg

a’a’e’e’

b’b’d’d’

c’c’

ss rr

qqpp

PP

SS QQ

RRDD

EE

AABB

CC

XX4040

GG

90°90°

2 D2 D

3 D3 D

Draw the Iso.View of a regular Pentagonal plane of 40mm sides, with one side normal to V.P. & the plane is in H.P.

4040X Y

aabb

cc

ddee

OO

O’O’

a’a’e’e’

b’b’d’d’

c’c’

PP

SS QQ

RRDD

EE

AABB

CC

OO

XX

6060

60604040

4040

Draw the Iso.View of a Pentagonal Pyramid, having base sides 40mm, axis 60mm long, when its base is in H.P.with a side of it normal to V.P.

2 D2 D

3 D3 D

X Y

gg

GG

g’g’

Aim:-Aim:- Figure shows the orthographic Figure shows the orthographic projections of a cut simple block. Draw its projections of a cut simple block. Draw its appropriate Pictorial ( Isometric ) view, appropriate Pictorial ( Isometric ) view, giving the dimensions. giving the dimensions.

NOTE:NOTE: The appropriate Isometric will be, considering its R.H.S.V.

( which is not given & is to be added as a missed view).

15

20

15

30

55 T.V.T.V.

11 22

33

FigureFigure

1520

60

55

F.V.F.V.

bb cc dd

aa

AA

BB

R.H.S.V.R.H.S.V.55

Normally, dotted lines are not drawn in Iso. View, unless specifically required to reveal the object perfectly.

15

15

15

20 30

35

bb

30 5540

11

22

33

aa

ddXX

cc

AA

BB

20

ISOMETRIC VIEW

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

15

20

15

3055

T.V.T.V.

11 2233

1520

60

55

F.V.F.V.bb cc dd

aa

Figure shows Front View

and Top View of a machine

parts. Sketch its isometric

view & dimension it.

7070 2020

1010

10102020

2020

T.V.T.V.

F.V.F.V.

AA

BB

DD

aa

bb11

bb22

cc

CC

SQ.HOLE OF 20 SQ.HOLE OF 20

2020

7070 20203030

3030°°

R25R25

2525

DD

2020

CC

2020

2020

aa

bb11

bb22

cc

AABB9595

1151155050

2525 3030 2020

SQ.HOLE OF 20 SQ.HOLE OF 20

1010

3030°°

XX

ISOMETRIC VIEWISOMETRIC VIEW

Aim:- SketchSketch shows the Orthographic

views of a machine component. Draw

its appropriate Isometric view, using

“splitting the object into pieces”

techniques. Give the dimensions on

the ISOMETRIC VIEW drawn.

SketchSketch

30

10

2080

F.V.F.V.

T.V.T.V.

20

R40

2040

20

30

5090

40

R.H.S.V. (missed view) may be added here in height & depth range

40

25

30

25

2020

R40

20

AA

CC

BB

DD

Ø30

50

70

90

8020

50

R15

25

20

10

20

30

Dimensions must be given on the Isometric view, which are not shown here.

80x80 square

NOTE:- The front view areas are AA & BB, while the side view areas are a, b & c.

1515

2525 6060

6060

120120

1515

L.H.S.V. L.H.S.V.

aabb

cc

AA

BB

FIGUREFIGURE

8080

Ø30Ø30 R30R30

35352020

4040 10104040

FRONT VIEWFRONT VIEW

aa

SolutionSolution

ISOMETRICISOMETRIC VIEWVIEW

bb

cc

AA

BB

R30R30

10102525 2020

2020

1515

8080

3535

120120

ø30ø30

XX

4040

4040

1515

6060

2020

F.V. L.H.S.V.

c1’

L= 60 mmH= 25 mmD= 34 mm X

3460

25