# Problem 7.5 Section of Solids

Problem 7.5 Section of Solids – A solid is a combination of half cone with base diameter 80 mm and half hexagonal pyramid with side of bade 40 mm & axis height 110 mm is resting on its base on H.P. such that one of the sides of the half hexagonal pyramid is perpendicular with V.P. It is cut by one AIP with inclination of 40° with the H.P. and passing at the distance 20 mm above the base & on the vertical axis. Draw front view, sectional top view and true shape of the section.

## Procedure:

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

Step-2 Draw a half hexagon of side of base 40 mm below the x-y line at some suitable distance from it, such that the one of the sides of the hexagon should be perpendicular with x-y line. And draw a half circle of diameter 80 mm such that it should be attached with the previously drawn half hexagon. Then find the center point of the assembly and connect all the corners of the hexagon to the center of the assembly by straight lines as shown in the figure. Give notations on it.

Step-3 From the center of the assembly, draw a vertical center line of length 110 mm from the x-y line as shown into the figure. And from these notations of  the assembly draw vertical projectors up to x-y line, and then converge all these projectors at the end of the center line i.e. apex of the front view (point o’) as shown into the figure. It is a triangular shape. And Give the notations on it.

Step-4 Draw a cutting plane line passing at the distance 20 mm above the base & on the center line of the assembly  in front view, such that its inclination with the x-y line should be equal to 40°, as shown into the figure.

Step-5 Give the cutting points name at the intersection of the previously drawn cutting plane line with the vertical projectors of the assembly  in front view, i.e., 1’, 2’, 3’ etc. as shown into the figure.

Step-6 From these points of intersections, draw vertical downward projectors in the top view such that these projectors will intersect with the respective lines in the top view. Now connects all these points in sequence by giving notations with straight lines or smooth free hand curve as per the shape of the cutting section, as shown in the figure. And draw hatching lines in the shape obtained. It is Sectional Top View.

Step-7 Now draw a line x’-y’, parallel with the cutting plane line in the front view, which should be outside of the boundary of the front view as shown into the figure. From the cutting points, i.e., 1’, 2’, 3’ etc., in the front view draw projectors which should be perpendicular to the cutting plane line and should be of some suitable length as shown into the figure.

Step-8 Now measure the distance of the cutting points from the x-y line, into the Sectional Top View and transfer the same at the respective  projectors drawn from the cutting points in the front view, on the previously drawn x’-y’ line, which is parallel to the cutting plane line in the front view.

Step-9 Connects all the points in sequence with medium dark straight lines or smooth free hand curve as per the shape of the cutting section, as shown in the figure, and draw hatching lines in it. It is the True Shape of the section.

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

## Author: Vasim Machhar

An Engineering Drawing Geek. Working at Noble Group of Institutions, Junagadh as Head of Mechanical Engineering Department.