 Hello everyone, Myself Professor Prithish Chittay working in Mechanical Engineering Department at Vulture Institute of Technology. In this session we will learn the methods of taper turning. So there will be the two sessions, taper turning one and taper turning two. So in this session what we will learn? These are the learning outcomes. So the students will be able to explain the different methods of taper turning, cutting operation on the job. Also they can solve the problem based on the methods of taper turning operation. We will have a quick recap of the third session and after that we will move towards the taper turning operations and their methods. Now what we have learned in the third session? We have learned the different lathe operations like there are the external cutting operations like turning, facing, taper turning, threading. So parting off operation, knurling operation, these are the external cutting operations. There are the different internal cutting operations like drilling, boring, internal threading operation. These are the internal cutting operations. You can see the different figures here. This is the figure of the facing where the tool is having the motion parallel to the axis of the rotation. Here there will be the relative motion between the tool and the workpiece. There will be the cutting operation. Here the diameter will be reduced. In the facing operation there will be the diameter will be reduced. In the facing operation the tool is moving perpendicular to the axis of the rotation. The workpiece is rotating and the tool is moving in the perpendicular to the axis of rotation. Here the length will be reduced in the facing operation. This is the boring operation which is the internal cutting operation where suppose you want to enlarge the hole which is already drilled with the help of drilling operation. So suppose you want the enlargement of the hole yes you can provide the boring operation. Boring bar is used and the boring tool is attached to the boring bar. This is the drilling operation suppose you want to provide the hole on the maybe the work piece. So this is the drilling operation you can see the particular animation of the knurling tool. The knurling tool is there which is fixed in the tool post and here the tool is moving perpendicular to the axis of the rotation and this one is last one will be the parting of operation. Parting of operation is the separating the work piece from the raw material. So these are the particular length operations. Now just go through the question identify the following length operation which is shown in the below here just think about this question we have discussed this already. In this session we will learn the taper turning what is mean by taper turning what are the different methods of taper turning taper means a conical shape work piece you can see the conical shape work piece which is having a two diameters d1 and d2 are the two diameters d1 is the major diameter d2 is the minor diameter and the taper will be d1 minus d2 means the difference between means the difference between the two diameters that is d1 and d2. So that is called as taper means you are having the slope here if suppose you are having a very simple job that is called as a very cylindrical job with the help of facing or maybe the turning you can provide the cylindrical type of job but whenever you are having the conical type of shape in that case you have to use the taper turning. So this will be the total taper that is d1 minus d2 divided by alpha alpha is your taper angle alpha is your taper angle l is the taper length so taper angle is equal to tan alpha is equal to d1 minus d2 divided by 2l so alpha is equal to tan inverse of d1 minus d2 divided by 2l now there are different methods of taper turning first one is Telstock setor method by swiveling the compound rest using the taper turning attachment there is a different attachment for the taper turning operation and using the form tool or maybe the broad nose tool so we are dealing with the two sessions for the taper turning so in the first session we will see the Telstock setor method and a form nose tool method now what is taper turning by Telstock setor method as we know that with the help of taper turning you can get the conical type of work pieces the cylindrical conical type of work pieces now this is a dead center which is a part of Telstock now this is a head headstock part where the live center is there this is a lead dog and this is the driving plate at the end of the driving plate the lead dog the tail of the lead dog is attached here now so what type of taper we can get here suppose you want to provide the taper turning operation very short length in that case you can use the taper turning by Telstock setor now what is the working principle so you can say so there is a nut which is provided to the Telstock and you can lose that nut and you can slide that Telstock maybe the away from the operator or maybe towards the operator if suppose you want the larger taper so you should take the Telstock away from the operator so that you can get the larger taper turning operation and if suppose you want the taper turning operation for very short length or maybe the short angle in that case take a Telstock or a slide a Telstock just towards the operator by losing the nut which is present in the Telstock and the tool will be moving parallel to the axis of the rotation but the work piece will be having the angle because your dead center is somewhat maybe in the inclination by alpha angle so whenever the tool is moving in the parallel to the axis of the rotation of the job there will be the taper turning operation and you will get the conical type of job so very simple derivation regarding the taper turning by Telstock setor so we are knowing that x is equal to L sin alpha this is L sin alpha where it's x is equal to length of the Telstock set over we have to calculate the length of the Telstock set over but here alpha is very small that's why sin alpha is equal to tan alpha so we can call that x is equal to L time alpha also we know that the taper angle is equal to or the tan alpha is equal to d1 minus d2 divided by 2l so with the help of this replacing the tan alpha by this equation or the term so x is equal to L into d1 minus d2 divided by 2l and x is the length of the Telstock set over and x is the length wherever you want to slide this Telstock may be the away from the operator or maybe the towards the operator that is the length of the Telstock set over so this is regarding the taper turning by Telstock set over you'll see the some examples calculate the Telstock set over length for taper turning operation such that the two diameters are 80 mm and 50 mm where length of the job is the 300 mm and length of the taper portion is the 200 mm you are having the d1 is 80 mm and d2 is 50 mm and capital L is 300 mm and small l is equal to 200 mm we are knowing that x is equal to L into d1 minus d2 divided by 2l and by that we can get x is equal to 15 mm by providing the values in the this equation and which will be length of the Telstock set over this is another example we are having d1 and d2 that is 3 by 2 inches and this is 5 by 4 inches capital L is that is the total length that is 10 inches and small l that is the taper portion length that is 5 inches providing these values in x that is l is equal to or l into d1 minus d2 divided by 2l we are getting the 0.25 inches that is the length of the Telstock set over now the taper turning by the form of the broad nose tool so this is the second method in the first method we have learned that the taper turning by the taper turning by the Telstock set over in this session we will learn the taper turning by form tool or may be the broad nose tool this is the broad nose tool this is the workpiece which is rotating in the check may be a three jaw check or may be the four jaw check or may be the magnetic check now you can see the the feed which is parallel to the axis of the rotation now you can see the form tool or may be the broad nose tool which is having already the angle alpha so whenever you are having the relative motion between the the form tool and the workpiece you will get the tapered portion for the workpiece but the disadvantage is that you can provide only the tapered operation for very smaller length up to 20 mm only so there is a limitation for this taper turning operation with the help of method that is called as taper turning by form or the broad nose tool as I say is that which is useful for very short length the tool consists of the half tapered angle and during this taper turning operation there will be the some of the vibrations or the chatter during the cutting operations and the limitation is for the 20 mm taper only so these are the references thank you