Top view and front view of line AB, 70 mm long measures 55 mm and 60 mm respectively. Draw its Projections if end A is 15 mm above HP and 20 mm in front of the VP. Determine its inclination with HP and VP.

Q. 5

Given Data:-

Top View = ab = 55 mm

Front View = a’b’ = 60 mm

TL = a’b1’ = ab2 = 70 mm

a’ (↑) = 15 mm

a (→) = 20 mm

Top View = Plan Length = ab1 = 55 mm

Front View = Elevation Length = a’b2’ = 60 mm

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

1. Draw XY line.

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

3. Draw horizontal line (Locus of a’ and a) from a’ and a respectively.

4. Mark EL (a’b2’) at 60 mm from point a’ on the horizontal line passing through a’ (locus of a’).

5. Mark PL (ab1) at 55 mm from point a on the horizontal line passing through a (locus of a)

6. Take the projection of b2’ into TV (Draw a vertical line from point b2’).

7. Take the projection of b1 into FV (Draw a vertical line from point b1).

8. TL is given in the problem, taking TL (70 mm) as radius and a’ as centre cut the vertical line passing through b1, mark that point b1’.

9. Join a’b1’ (TL).

10. Draw the locus of b’ (Horizontal line passing through b1’).

11. Taking TL (70 mm) as radius and a as centre cut the vertical line passing through b2’, mark that point b2.

12. Join ab2 (TL).

13. Draw the locus of b (Horizontal line passing through b2).

14. Taking a’ as center and a’b2’ as radius draw an arc which will cut the horizontal line passing through b1’ (Locus of b’), mark that point b’.

15. Join a’b’ (FV).

16. Taking a as center and ab1 as radius draw an arc which will cut the horizontal line passing through b2 (Locus of b) mark that point b.

17. Join ab (TV).

18. Draw horizontal line from b’ and b and name it locus of b’ and locus of b respectively.

19. Take the projection of b1 into FV (Draw a vertical line from point b1) which will cut the locus of b’. Mark that point b1’.

20. Measure true inclinations θ and Φ.

    Answers – i) θ = 38° ii) Φ = 31°