Question

A line measuring 80 mm long has one of its ends 60 mm above HP and 20 mm
in front of VP. The other end is 15 mm above HP and in front of VP. The front
view of the line is 60 mm long. Draw the projection of straight line and also
find the true inclinations with H.P and V.P.

Answer 1

Answer:

Distance between End Projectors (DBEP) = 40 mm

a’ (↑) = 15 mm

a (→) = 20 mm

θ = 30°

TL = ab2 = a’b1’ = 80 mm

Follow the procedure given below step by step to draw the projection of line –

Draw XY line.

Mark a’ and a at 15 mm above XY line and 20 mm below XY line respectively.

Draw horizontal line from a’ and a.

Draw TL (a’b1’) of 80 mm from point a’ at an angle of 30°.

Draw locus of b’ through point b1’.

Mark a point at DBEP = 40 mm measuring from point a’ and draw a vertical line from that point.

This vertical line will cut the locus of b’. Mark that point b’.

Join a’b’ (FV).

Taking a’ as center and a’b’ as radius draw an arc which will cut the horizontal line passing through a’, mark that point b2’.

Join a’b2’ (EL).

Take the projection of b1’ into TV (Draw a vertical line from point b1’) which will cut the horizontal line passing through point a. Mark that point b1, ab1 is your plan length (PL).

Taking a as centre and ab1 as radius draw an arc which will cut the locus of b, mark that point b. Join ab, that is your TV.

Draw a horizontal line from point b, that is your locus of b.

Take the projection of b2’ into TV (Draw a vertical line from point b2’) which will cut the locus of b. Mark that point b2.

Join ab2 (TL).

Measure the true inclinations Φ.