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INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY Department of Mechanical Engineering

ME-119 Engineering Drawing & Graphics 2012-13 Semester II

Sheet 8: Development of Surfaces Note: Practice all problems roughly before coming to the Drawing Session. For more

details of the exercises in this sheet, refer Chapter 14 of the text book (N. D. Bhatt, Engineering Drawing, 50th Ed.).

Approximate time required to complete the problem neatly in the drawing hall is specified under each.

Lettering, dimensioning and line types shall be as per the standards discussed in Chapters 1-5.

Draw all 10 problems in the drawing hall under supervision and submit for grading. Refer to the figure given at the last page for problems 2, 4, 6, 8 & 10. Assume each

square to be of 10 mm side.

1. Draw the development of the lateral surface of the hexagonal prism with the base 20 mm

side and 40 mm height. The hexagonal base lies in H.P. and longest diagonal of base is

parallel to V.P. It is cut by two planes such that as we move from bottom to top, the

inclination changes from 30° to 60° at the midpoint of the axis in the front view.

(Source: Solved Pb. 15-5, pp. 355) [10 min]

2. Draw the development of the surfaces of the portions of the following prisms, front views

of which are shown in the top row:

(i) A hexagonal prism having a face parallel to the V.P. [Fig (a)]

(ii) A hexagonal prism having two faces perpendicular to the V.P. plane. [Fig (e)]

(Source: Exercise Pb. 15-5, pp. 378) [20 min]

3. A frustum of a square pyramid has its base 50 mm side, top 25 mm side and height 75

mm. Draw the development of its lateral surface. Also draw the projections of the frustum

(when its axis is vertical and a side of its base is parallel to the V.P.), showing the line

joining the mid-point of a top edge of one face with the mid-point of the bottom edge of

the opposite face, by the shortest distance.

(Source: Solved Pb. 15-21, pp. 364) [10 min]

4. Draw the development of the surfaces of the portions of the following pyramids, front

views of which are shown in the second row:

(i) A hexagonal pyramid having a side of base parallel to the V.P . [Fig (b)]

(ii) A square pyramid having all sides of the base equally inclined to the V.P.

[Fig (e)]

(Source: Exercise Pb. 15-6, pp. 379) [20 min]

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5. Draw the development of the lateral surface of the cylinder cut such as shown in fig.1.

(Source: Solved Pb. 15-12, pp. 358) [10 min]

6. Draw the development of the surfaces of the portions of the cylinder shown in fig. (c) and

fig. (e), in the third row.

(Source: Exercise Pb. 15-7, pp. 380) [20 min]

7. Draw the projections of a cone resting on the ground on its base and show on them, the

shortest path by which a point P, starting from a point on the circumference of the base

and moving around the cone will return to the same point. Base of cone 61 mm diameter

and axis 75 mm long.

(Source: Solved Pb. 15-26, pp. 367) [10 min]

8. Draw the development of the surfaces of the portions of the cones shown in fig. (c) and

fig. (e), in the fourth row.

(Source: Exercise Pb. 15-8, pp. 380) [20 min]

9. Three cylindrical pipes of 50 mm diameter form a Y-piece as shown in Figure 2. Draw the

development of the surface of each pipe.

(Source: Solved Pb. 15-14, pp. 360) [20 min]

10. Refer to the fifth row, and

(i) Draw the development of the pipes forming a Tee shown at fig. (a).

(ii) Draw the development of the three parts of the funnel shown at fig. (c).

(Source: Exercise Pb. 15-9, pp. 380) [30 min]

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