Problem 6.8 Projection of Solids

Problem 6.8 Projection of Solids – A pentagonal prism of side of base equal to 40 mm and axis height 110 mm rests on one of its corner of its base on H.P. such that the axis is inclined at an angle of 40° with H.P. and 60° with the V.P. Draw its projection.

Procedure:

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

Step-2 Draw a pentagon of side of length 40 mm, below the x-y line at some suitable distance such that one side of the pentagon should be perpendicular with the x-y line, as shown into the figure. And give the notations. It is the top view of the 1st stage.

Step-3 From the notations of the pentagon in top view, draw perpendicular vertical projectors of the length equal to 110 mm from x-y line, and connect all the points in sequence with straight lines 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 center line of the pentagonal prism should be inclined at an angle 40° with the x-y line, and the corner of the prism that is d’ should touch with the x-y line, as shown into the figure. And give the notations. 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 straight lines between all the points in sequence as shown into the figure. It is the shape like a pentagonal prism. But be careful that some of these lines are dotted lines because of hidden.  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 center line should be inclined at the angle 60°, as show into the figure with the same dimensions and the top end of the pentagonal prism should be near to the x-y line as shown in the figure. 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 straight lines between all the points in sequence as shown into the figure, It is the shape like a pentagonal prism, as shown into the figure. But be careful that some of these lines are dotted lines because of hidden. 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.