Q.(7) Two views of a square prism of base side 40 mm and axis height 80 mm are given as
below in the third angle method. Cutting plane is given in the F.V.
Draw it's a) F.V.
(3 marks )
b) Sectional TV
( 6 marks)
c) Sectional R.H.S.V.
( 6 marks)
d) True shape of the section
(5 marks )
e) Development of the remaining portion
( 6 marks)
Answers
Answer:
Given Data
Side of prism = 40 mm
Axis length = 60 mm
Resting on one of its corner = HP
Axis inclination with HP = 30°
Stage 1
Draw XY line.
A prism is resting on HP, so square will be seen in TV and rectangle in FV.
Draw TV as a square two sides equally inclined to VP (side 14 and 13 inclined 45° to XY line). (If the prism is resting on side of base then the initial position in TV would be different).
Name the square 1 2 3 4.
Take the projections of all corners into FV.
Complete the FV taking axis length 60 mm.
Name the FV on both top base as well as bottom base 1’ 2’ 3’ 4’.
Stage 2
As axis is inclined at 30° to XY line the line 1’3’ will be at 60° to XY line.
So first mark point 3’ at some convenient distance on XY line. Then draw line 1’3’ at angle of 60°, so that the axis will be inclined at 30°.
Using compass mark points 2’ and 4’ on the line 1’3’.
Complete the FV in inclined position using compass.
Take the projections of all 8 points 1’2’3’4’ from both the bases in TV.
Take the horizontal projections of square corners towards right side.
Intersection of 1 and 1’ will give point 1, Intersection of 2 and 2’ will give point 2, Intersectionof 3 and 3’ will give point 3, Intersection of 4 and 4’ will give point 4 for both the bases.
Sides of bottom base 2 3 and 3 4 will not be visible in TV, also vertical edge 3’3’ also not visible. Draw this lines as hidden lines.