 Hello, I am Mr. D.J. Doshi working as assistant professor, department of mechanical engineering Valginist of technology, Solaapur. Now, we will be studying about projection of solids. At the end of this session, students will be able to draw the projections of the solids as per given conditions. First problem, pentagonal prism having age of base 25 mm, axis height 60 mm, has one of its corner in HP. The axis is inclined at 30 degree to HP and the top of the an axis inclined at 45 degree to VP draw the projections. Now, here if you see the pentagonal prism is resting on HP and the axis is making certain angle at this 30 degree to HP. So, first we will go for first stage that is we will consider that the axis of the prism is perpendicular to HP and parallel to VP. So, initially we will draw the first stage as a prism resting on HP, a pentagonal prism resting on HP. Now, here again as it is resting on one of its corner of the base, while drawing pentagon you have to take care that the corner will be towards your right hand side because we will be making angle of prism with HP by rotating or tilting the prism towards your right hand side. So, while drawing the first stage as we as I said we will consider that prism is resting on HP and the axis is parallel to VP and perpendicular to HP. So, first stage is top view will be drawing a pentagon. So, pentagon you will draw with included angle as 108 degrees. So, complete the pentagon with the given base size that is 25 mm. So, accordingly we have completed 1, 2, 3, 4, 5 is the pentagon drawn as a top view. Projected upwards you will get two base edges that is bottom base edge and top base edge. So, you will get two horizontal lines representing the base and top edge join those points. So, it will be 1 dash, 1 dash, 2 dash, 2 dash, 3 dash, 3 dash, 5 dash, 5 dash and 4 dash, 4 dash. So, this will be the front view of the pentagon resting on HP and draw axis line as shown in the figure. Now, second stage what is second stage axis is inclined at 30 degree to HP. So, we will incline the prism to 30 degree to HP for that we have to rotate the prism and redraw the same sketch by making 30 degree with HP, but you should take care that 0.4 must not leave the line XY it should be resting on HP only. So, instead of making angle by axis line that is 30 degree you can make the angle of 4, 4 dash that is one of the generator making 30 degree with HP and draw the sketch and later on you can complete the axis. Or if another thing as axis is making 30 degree axis is perpendicular to base it is 90 degree. So, another angle which is made by the base with the HP or with the XY line will be 60 degree. So, you can refer any of these three options while redrawing the prism, copy of the prism and draw 4, 4 dash, 3 dash, 3 dash, 5 dash, 5 dash, 2 dash, 2 dash and 1 dash and complete the tilted view of the prism which is second stage first view that is front view of the prism when axis is making 30 degree. Now, project 1 dash downwards vertically then project 1 and 2 from the first stage top view draw it horizontally you will get the intersection points as 1 and 2. Similarly, 3 and 5 are the points of the base you project it downwards project 3 and 5 the points on the top view from the pentagon horizontally you will get the intersection points that is 3 and 5 and project the resting corner that is 4 from the pentagon shown in the top view draw vertical projector from the second stage first view that is 4 point 4 dash downwards you will get point 4. So, now as if you observe point 4 is away from the observer or it is resting on the soil line. So, when you observe it from the top for getting the top view you will not see the line drawn from 4. So, that line through the 4 there are 3 lines which are passing through point 4. So, 3 4 and 4 5 will be dotted line and similarly 4 4 also will be dotted line. So, now again for the top face of the base project again similarly 1 dash 2 dash downwards horizontally 1 and 2 you will get 1 2 line of the top face similarly 3 and 5 will be projected downwards draw the horizontal projectors through 3 and 5 you will get point 3 and 5 and project 4 from the top face you will get point 4. Now, as the observer observing for the top view you can see that 1 2 3 4 5 of the top face will be totally visible. So, you have to join 1 2 2 3 3 4 and 4 5 with the dotted lines. Now, draw join 5 5 1 1 2 2 3 3 and 4 4 will be joined with the dotted lines. So, this completes the second view that is the axis making 30 degree angle with h p. Now, we have stage 1 and stage 2 drawn for third stage it is given that the object is making angle of 45 degree with the v p that is top view of an axis is inclined at 45 degree to v p. So, now if you observe in stage 2 top view the axis line and the generator 4 4 dash on the same or on the same line. So, draw a 45 degree line making angle with h p that is in h p or making angle with 45 degree with x y line in the top view and take a point at one place from there redraw the same sketch which is in second stage top view. So, first you will draw the 4 4 dash line and accordingly complete the pentagonal top views of top face and bottom face and complete the redraw process. Now, we will go on projecting the points 1 2 3 4 5 of the top face and 1 2 3 4 5 of the bottom face. Similarly, we will project 1 dash 2 dash 3 dash 4 dash and 5 dash horizontally from the front view and of the top face and points 1 2 3 4 5 of the bottom face in the front view. You will get the intersection points and accordingly we will complete the drawing of 1 dash 2 dash 3 dash 4 dash 5 dash as top face and 1 dash 2 dash 3 dash 4 dash 5 dash as bottom face. Now, while joining the lines that is 1 1 dash 1 dash 2 dash 2 dash 3 dash 3 dash 4 dash 4 dash and 5 dash 5 dash you have to take care that which of the part is to be drawn as dotted line. Now, if you observe for the front view the top view drawn when you observe it the top view drawn you can see that the line 5 5 the point 5 of the face is away from the observer. So, 5 5 dash will be dotted line then 5 dash 1 dash and 5 dash 4 dash will be the dotted lines. So, take care while drawing that 5 dash 5 dash and 5 dash 4 dash and 5 dash 1 dash in the top face will be dotted lines other lines will be 3 lines and accordingly we will complete the final view when the prism is making 30 degree with the HP and the axis is making a top view of the axis is making 45 degree with VP. Accordingly we will complete the projections of the solid as per given in the problem. Now, similar case is related to the cylinder a right circular cylinder diameter of base 50 mm axis 70 mm has one of the circumference point on base HP such that the axis is inclined at 30 degree to HP and axis appears to be inclined to 45 degree to VP similar process, but here we do not have generators as per pentagonal prism or hexagonal prism. So, here we will divide the circle into 12 parts projected upwards and we will get the generators on the front view also again it is given that axis is axis is making 30 degree with HP. So, draw a 30 degree line again same thing the base will be drawing base will be making 60 degree with the horizon. So, as per last problem you can repeat the same thing draw in base or draw an axis making certain angle. So, axis is 30 degree whereas, bottom base will be making 60 degree with HP or x y redraw the cylinder front view projected downwards you will get the ellipse as a top view of a circle both the circles, but again the point which is away from the observer is 7. So, while completing the top view you have to take care that the dotted line will be from 4 7 10 and other generators will be or other ellipse and other parts will be dark line again the axis is making 45 degree with the VP. So, draw a 45 degree line redraw the cylinder top view drawn in the second first second stage sorry second stage redraw it projected upwards here you will observe that point 10 is away from the observer. So, the related lines will be dotted lines and complete the ellipse. So, similar process only here we do not have generators and accordingly you have to complete stage 1 stage 2 and stage 3. Thank you.