Machine Drawing

Principles of Drawing 15

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d:\N-Design\Des2-1.pm5 Seventh Print

D1

K1

D1 B1

B6

J1 G1

A1

B4

G1

E1

G3

B2

G2

K2

B2

B3

B5

B7

Y

Y–Y

Y

Fig. 2.5 Applications of lines

K3

C1

Fig. 2.6 Applications of lines

2.4.1 Thickness of Lines

Two thicknesses of lines are used in draughting practice. The ratio of the thick to thin line

should not be less than 2:1. The thickness of lines should be chosen according to the size and

type of the drawing from the following range:

0.18, 0.25, 0.35, 0.5, 0.7, 1, 1.4 and 2

It is recommended that the space between two parallel lines, including hatching, should

never be less than 0.7 mm.