Textbook of Engineering Drawing, Second Edition

-----____ Geometrical Contructions 4.11

B

p

Q

Fig. 4.17

c

16. To draw an arc of a given radius, touching two given straight lines making an angle
    between them.
    construction (Fig 4.18)
    Let AB and CD be the two straight lines and r, the radius. Draw a line PQ parallel to AB at
    a distance r from AB. Similarly, draw a line RS parallel to CD. Extend them to meet at O.
    With 0 as centre and radius equal to r draw the arc to the two given lines.

c

17. To draw a tangent to a circle
    construction (Fig 4.19 a and b)
    (a) At any point P on the circle.

(a)

8

Fig. 4.18

Fig. 4.19