A cone base 50 mm diameter and axis 60 mm long rest on its circular rim on the HP with the axis making an angle of $30^0$ with the HP and its top view making an angle of $45^0$ with the HP. Draw its projections.

Q. 7

Given Data

Diameter of cone = 50 mm

Axis length = 60 mm

Resting on circular rim on HP

Axis inclination with HP = 30°

Top view of an axis is inclined 45° with VP

Stage 1

1. Draw XY line.

2. Cone is resting on HP, so TV will be a circle and FV will be a triangle.

3. Draw TV as a circle of diameter 50 mm.

4. Draw vertical and horizontal axis of circle.

5. Divide the circle into 12 equal parts (You can divide it into 8 parts also). Name all the points 1, 2, 3,….12.

6. Take the projections of all point into FV.

7. Complete the FV taking axis length 60 mm. Draw all the generators of cone.

8. Name the FV of cone on base as 1’ 2’ 3’….12’ and O’ as apex.

Stage 2

1. As axis is inclined at 30° to XY line the base line 1’7’ will be inclined at 60° to XY line.

2. So first mark point 7’ at some convenient distance on XY line. Then draw line 1’ 7’ at angle of 60°, so that the axis will be inclined at 30°.

3. Using compass mark all the points from stage 1 to stage 2 on line 1’ 7’.

4. Complete the FV in inclined position using compass.

5. Take the vertical projections of all 12 points 1’, 2’, 3’, …12’ and apex points O’ in TV.

6. Take horizontal projection all points along with apex towards right side from the TV of 1st stage.

7. Mark the intersection points 1,2,3..12 and apex O.

8. Draw a smooth curve passing through all the 12 points.

9. Join end generators with apex.

Stage 3

1. Now in third stage the top view of an axis is inclined to VP.

2. Draw a line inclined at angle of 45° to XY line.

3. Mark point O at some convenient distance below XY line.

4. Using compass complete the TV in inclined position

5. Take the projection all points along with apex into FV.

6. Take the projection all points along with apex towards right side from the FV of 2nd stage.

7. Mark intersection points 1’ 2’ 3’, ...12’ and apex O’

8. Draw a smooth curve passing through all the 12 points.

9. Join end generators with apex O.