 myself, S.M. Watt, assistant professor, Walsh and the Institute of Technology, Solaapur. Today, I am explaining through this video, the orthopedic projections. In the orthopedic projections, next step of this one, that is the sectional view, we have to draw it here. Why the sectional view, we have to required? Because some surfaces have to be there, they are hidden one, they are not directly come into the surfaces. And when these surfaces not come to the surfaces, not in shown, it is not clear that object, that part. So, that is why we have to go for a sections of this one. The basic learning outcome of this one is, student will able to draw the orthopedic projections of a sectional view of the simple object. Now, here I mean showing this object, this isometric view. So here, you have to draw the front view in the direction of x and a section, you have to take on it here, section, the section line is to be shown here, a a, this portion is to be there. From this portion, you have to cut this half portion, half portion you have to cut it and you have to draw the section of this one. So first of all, you have to calculate the maximum dimensions in the direction of f. The maximum dimension is given as, it is the r15 from the center line, 15 plus 15, that is the 30, from 30 plus 15 center line, 45, 45 plus this is r15, that is the 60. So this length is 60, width is 60 and length height is given as r15, 15, center to center distance 45. So 15 plus 45, that is 60, 60 plus 15, 75. So take height as a 75, height is 75 and total width is given as 15 plus 15, 30, 30 plus 15 plus 15 is 60 and the height is 75. So you make a block of this one. Now this portion, which is to be seen here, I am hatching up this one, this is the front view. So this portion, you have to cut it here, but the hidden portion that comes into surfaces. So that part is seen as it is. So you have to go for a circular portion r15 with a radius 15. So first you have to locate the center line of this one, this portion center line, this center and center matching one, that is r15. From this end, you have to move 15 mm here and 15 mm from here. So you have to complete this one, semi-circular part of this one. Take a diameter of radius as a 15, that is total width, total, how much where it is extended. So this portion, this width is to be 10 mm. One more center line, the circular hole is to be there, matching one. That is to be given as 515, four holes are there, 1, 2, 3 and 4. That diameter is 5 to 10. So radius is 7.5, okay. This part is over. Now this portion remaining, actually it is perpendicular to square block and the width is given as a 10 mm. So from this end it is a 10 mm, it is up to here. And how height is extended, how much it is extended, it is given that the center to center distance is 15 and this height is to be given as a 10 mm. So total height is given as 45. So 15 plus 45, center to center, this center is 45 from here. So from this center to center 45, it is to be here and center of this one. So 45 divided by 2, that is 22.5 from the top surfaces, 10 mm, 2 mm, 22, 22.5 mm. And it is the center mm and this width of this slab is given as it is given. How much it is? It is 10, 10, 10. So from the upward 10 mm and downward it is 10 mm. So total width is, sorry it is taken as a 5 mm and 5 mm from here and here. And extend this portion, okay. Now when you take a, this portion is to be there, when you see from this circular portion is seen as a rectangle and how much it is, this line is extend of its square block. Square block is to be there, okay. And center of there is hole and this hole is to be hidden one. So draw, how we have to show it? Suppose some portion is to be there that is not seen in the front view. The hole is there, surface is to be there. That is to be shown by which notation, think over that, pause the video and think over that. Yes. So when that, this hole is hidden one, it is to be seen that surface is hidden one, that edge is hidden one, that is to be shown by a dotted line. So that is why we have to draw the two dotted lines for this end and this end for this whole one. So two dotted lines are to be there with the center line. So first we have to fix the center line. Center line is, R is 15 mm. So from this end you have to fix the center line that is 15 mm. This is to be here. And radius is given as it is given as four holes are there, 5, 15. That is 7.5 radius and it is to be seen by a dotted line. Again here also for this edge or this surface, again it is a hidden one, again it is to be dotted one. So fix the center line. Center line is 15 mm, R 15 and the diameter is 515 that is 7, radius is 7.5, right hand left 7.5 and 7.5, they have to be shown by a dotted line. So this is a regular what you call orthopic drawings, that is a front view orthopic drawing. But you have to take a section of this one. So this portion is to be removed, you have to section of this one. So when this portion is removed, this surface again come, it is okay as it is, it is seen as it is. But what about this portion, this lab is to be cut. And when a hole is to be cut, the edges of these surfaces, this edge and this surface it is shown. It is seen as a dark one, instead of a dotted one it is a one surface is to be there, this portion. Then this surface, the circular portion is again it is perpendicular one, it is seen as a straight way, it is a rectangle one. And again this edge it is to be seen, okay. Now this slab is to be cut up to here and this portion is top of that. So it is a continuous one slab is to be there and this portion is one portion. And same thing, this circular hole it is to be cut that is not seen. This portion is to be seen, you have to cut this portion centrally. Again these surfaces in this surface they have to be seen as a dark one, the surfaces. So this portion is seen as a one continuous surfaces, we have to cut this one. So that portion you had, I am showing here as a section one. So this surface come to here, the circular portion that come to the surfaces that is again parallel to you. So it is a sectional front view, okay. So when you know this one then you have to go for, so when you have to cut this portion sectional front view is there. Now as it is regular you have to go for the top view. In the top view you get as a two rectangular slabs are there, extend this one, centrally the circular portion is to be there. Take this radius of this one, how much this radius is given as, you get as a circular portion is to be here and two slabs are there, two rectangles are to be there. So today basic concept is to be to clear the sectional view of the cut portion is to be there. When you have to cut this portion, so this surface seen as surface of cut portion, the circular portion seen as one of the surface rectangle and remaining the slab is to be cut and when this front portion, this portion is to be removed, the behind portion comes to here and that is to be seen as a front view, okay. So this is all about the sectional front view. In the next lecture we have to go for the sectional front view, top view and the side view. So for this one, references I am taking as a engineering graphics one by professor ML Dabare, why the vision publications are to be there. Thank you.