# Problem 6.9 Projection of Solids

Problem 6.9 Projection of Solids – A cone of  diameter of base 60 mm and axis length equal to 100 mm rests on one of its slant generators on H.P. such that its axis is inclined at an angle of 65° with the V.P. Keep its apex near to the V.P. and draw the projections.

## Procedure:

Step-1 Draw a horizontal x-y line of some suitable length.

Step-2 Draw a circle of diameter 60 mm, below the x-y line at some suitable distance, and divide this circle into 12 equal divisions, as shown into the figure. And give the notations. It is the top view of the 1st stage.

Step-3 From the center of the circle in top view, draw a perpendicular vertical projector of the length equal to 100mm from x-y line, and give the notations as shown into the figure. And from the notations of the circle in top view, draw perpendicular vertical projectors up to the x-y line. From these end points draw slant lines connecting to the apex point  “ o’ ”  in the front view, and give the notations as shown into the figure. It is the front view of the 1st stage

Step-4 Now copy the front view of the 1st stage as the front view of the 2nd stage with the same dimensions, such that the line o’- a’, should be parallel to the x-y line & resting on it, and the remaining drawing should be drawn accordingly as shown into the figure. It is the front view of the 2nd stage.

Step-5 From the notations of the front view of the 2nd stage draw vertical projectors into down ward direction and from the top view of the 1st stage draw projectors into horizontal direction as shown into the figure, which will intersect with each other at respective points.

Step-6 From these respective points of intersections, draw a medium dark smooth curve passing through the points a to h in sequence as shown into the figure. And connect the extreme two points i.e., h & c, with straight lines with the apex o as shown in the figure. And give the notations. It is the top view of the 2nd stage.

Step-7 Copy the top view of the 2nd stage as the top view of the 3rd stage at an angle 60° with the x-y line such that the apex of the cone should be near to the x-y line, as show into the figure with the same dimensions. And give all the notations on it. It is the top view of the 3rd stage.

Step-8 From the front view of the 2nd stage, draw horizontal projectors, and from the top view of the 3rd stage draw vertical projectors in upward direction, which will intersect with the previously drawn projectors at respective points.

Step-9 From these respective points of intersections, draw a medium dark smooth curve passing through the points a’ to h’ in sequence as shown into the figure. And connect the extreme two points i.e., d’&a’, with straight lines with the apex o’ as shown in the figure. It is the front view of the 3rd stage.

Step-10 Give the dimensions by any one method of dimensions and give the notations as shown into the figure.