in this lecture I will be discussing on fittings so what is feet the degree of tightness or looseness between cremating Parts is called feet to understand feet we have to first understand what is the meaning of interchangeability now suppose uh in a workshop you have to prepare two mating boards suppose one shaft and another one is whole okay and suppose the diameter of the shaft that we want to make is say 25 millimeter and the hole that we want to make is in which it is going to fit is also 25 millimeter but it is not possible to make exactly a shaft or a hole of size 25 millimeter so uh what is uh then recommended is some tolerance or the upper limit and the lower limit of these both shaft and the whole is mentioned in the drawing so that during manufacture a particular lot that this particular limit has to be maintained it is not required that it has to be saved exactly as the base size but within that limit if you make that Shaft or the whole then uh any uh hole or the shaft in that particular lot can be used as a mating component that means ah let us consider uh this is the for the whole suppose it is 25 which is the best size 25 millimeter which is of this size and its upper limit is suppose 0.02 and suppose it's a lower limit is say zero the lower limit is zero so it means that within uh 25 point zero two millimeter to 25.00 millimeter you can repair the whole and this 25.02 is called the upper debit and 25.00 millimeter is what is called the lower limit so 25 is the base size and you can make any hole within that uh there and the tolerance for this particular component whole is basically the upper limit minus the lower limit that means the tolerance is 0.02 minus 0 which is 0.02 so now it is clear that what we mean by the tolerance exactly in a similar way maybe for when a shaft is designated in a drawing ah it is actually coming with some tolerance value maybe uh it is point 0 1 and maybe the lower limit is minus point zero eight so this kind of specification for the shaft or for the whole can be given so you can understand that what is the maximum size of the shaft and what is the minimum size of the shaft within which you can make the shaft so this is the tolerance level that is mentioned along with the base size so that now uh what happens that a lot that is prepared uh with this particular specification or unlock the different lot maybe with a different set of machines that is creating the whole uh is prepared with this particular specification now for a particular kind of a feat any shaft from this lot and any hole from this slot can be the mating part in that particular assembly so this is what is the idea of interchangeability so the idea of interchangeability is that you can choose any component from that lot or any lot and another component from the other lot and they will be the meeting part in this way we can reduce the cost okay we can save money you can save time and that is why this kind of Tolerance and the uh fundamental deviation is uh specified now after understanding this part from this figure a few more terminologies which are related to that you can understand that let us consider this is a particular whole size you can see this is what is the base or basic size here you can see this is what is the basic size or the diameter the basic diameter in our example it is like 25 and ah this is the maximum this is the minimum value of the whole diameter this is the minimum value of the whole diameter that is to be there which is indicating the lower limit and this one is the maximum value of the whole diameter which is indicating the upper limit okay so in this picture you can see this is what is the lower limit from here to here this is the lower limit of the hole and this is the upper limit of the rule and this yellow region is basically indicating that this is what is the tolerance so here you can see uh as shown in the figure the base size with respect to the base size in this figure uh suppose it is 24 20 and maybe uh it's the tolerance level is such that plus may be 0.2 and this one is plus 0.1 so both the tolerance level can be positive as you can see here so uh upper limit and the lower limit and the tolerance is 0.2 minus 0.1 which is 0.1 so this yellow region is showing the tolerance of the hole exactly in a similar way you can see the maximum diameter of the shaft and the minimum diameter of the shaft are indicating the upper limit and the lower limit of the shaft in that particular load okay and the best size or the basic size is this one and that has to be mentioned along with the tolerance level now when the question comes related to uh the feet you can see that feet can be of three different kinds it can be of clearance fit or it can be of interference fit or it can be a transition pit so what is the meaning of the clearance speed whether clearance fee we mean that in a particular lot suppose this is lot one and this is another lot which is say Lord two so lot one suppose is producing the holes and the Lot 2 is produced in the shafts and if the feet is such that uh any com any hole that you can choose from the dot one any hole you can choose from the Lord one and if you choose any shaft from this block 2 you will always get a clearance between the hole and the shaft that means the whole size is greater than the shaft size if this is the situation for any particular field that is required then that particular feed is called the clearance feed so that means in a clearance speed it will be always the size of the hole will be larger than the size of the shaft here you can see this is the lower limit of the hole this is the lower limit of the hole and this is the upper limit of the hole okay and this is what is the base size of the hole so uh and this is nothing but the tolerance region of the hole that has been shown now you can see on the other hand for the shaft this is the maximum size of the shaft that can be uh prepared and this is corresponding the minimum size of the shaft this is the lower limit of the shaft and this is the upper limit of the shaft and here you can see the maximum size of the shaft is the maximum diameter of the shaft is less than the minimum diameter of the hole as you can see here in this diagram that the maximum diameter of the shaft is less than the minimum diameter of the hole so this particular feet which has been shown here is nothing but a clearance speed okay so we can see that what we mean by the clearance rate now on the other hand if you see the interference with in case of interference feed you can see that the shaft size is always greater than the whole size so from l 1 and L to 2 Lots L1 and L2 is such that any hole you choose from Lot 1 and any shaft you choose from the Lot 2 if you try to fit them you will find that this whole size is always less than the sharp sides that means it is not easy that you can push the shaft within the hood so always you have to give some external Force to insert the shaft within the pool so this kind for the Press fit is uh coming because of the interference of the shaft and the whole tolerance region so you can understand what we mean by the interference field now we come to the transition feed in a transition field you see that lot one and the Lot 2 is such that say Lot 1 is producing holes in the lot 2 is producing shaft but the Lord one having the tolerance region shown here so this is the tolerance region of the whole okay and you can see this is what is the lower limit right and this is the upper limit of the whole and this is what is the basic size of the hole or the shaft now you see that if this is the tolerance level of the hole and if the shaft tolerance level is like this if the shaft tolerance level is like this then you can see it is possible that the size of the shaft and the size of the hole can be either uh there is some clearance between the shaft and hole or there is some interference between the shaft and the pole pole so both are possible here also exactly in a similar way if the shaft tolerance level is like this so here also that same possibility that either interference or it can be clearance that is possible between the shaft and the hole and here also you can see that the all the possibilities are there so that is why this is called the transition heat that means both clearance as well as interference may be there if you try to fit this any component in the lot one with the shaft in the Lord okay so uh if the fifth is defined in such a way that this kind of Tolerance uh regime is coming then it will be under transition field now after understanding uh this much I hope you can understand what are the different types of feed ah that is possible now once we understand what is feet now the definition of fitting can be given very easily that fitting means it is the term fitting is related to the assembly of the parts okay and after bringing the dimension of the shape to the required size or form in order to secure the necessary fate the operation required for the same are usually carried out on workbench is called the fitting walk Okay so we can understand that different kinds of fitting operations uh through which we always try to change the dimension or change the shape so that our two mating Parts can fit according to the requirement and what are the different types of feed already we have C although uh in today's industry most of the work is done by the automatic machines that produces jobs with very good accuracy but still it requires some hand operations like fitting operations and the person who is doing the fitting operations are called a feeder now what are the different types of feeding operations and how they are performed that means with the help of different fitting tools how they are performed that we learned next so what are the different fitting operations possible like deburring operation measuring and marking punching sawing chiseling filling filing inspection drilling reaming tapping dime finishing you'll see all this one by one now first let us see what we mean by the deburring process the repairing is a process of removing the small imperfections known as bars from machine Metal Products rough find or the Bastard files okay so password files the picture of the Buster files you can see over there so this is a flat busted file and these are basically very rough files these are not generally used for very uh fines uh finishing work okay these files are respectively enough file so a wrap file or the Buster files are used to remove these parts here in this picture you can see these are the bars uh those are required to remove and these kind of bars are produced during Machining or casting or different works and finally after with the help of this uh the uh by the deburring process which is actually done with the help of the mustard file you can make this kind of finishing so this process is called the body so measuring can be of different kind and different kinds of tools are used for that so here in you can see that the length measurement and the scribing line we can do with the help of Steel rule at the scriber so steel rule already you know and with the help of a scriber we can draw straight line with the help of Steel rule so this is a very important ah measuring and the marketing process used then to check the flatness and the squareness we use the try square and here you can see the different parts of a tri square like this part is called the blade and this one is called the stock now coming to the ah few more measuring and marking tools here you can see that for the a precise measurement we can use the Vernier caliper or the micrometers and here you can see that there is a movable uh main there is a movable Vernier scale that is attached with the jaw and the main scale is there as well and for the external dimension we use the distance between these two jaw and for the internal Dimension we use these two ends like for a hold if we want to measure then you can see if this is the whole with the help of these two jaws we can measure and in that case definitely these particular Vernier attached with this particular job is used for the Vernier skill query for the inside Dimension we can also measure with the help of uh inside caliper here you can see the help of inside caliper we can measure some internal dimensions and for the external Dimension we can use the outside caliper and we can use the divider for transferring Dimension from one place to another place and also it is used to describing circle on a Surface as well for now and only a caliper or the hermaphrodite caliper here you can see this particular caliper having one level is built like this and this kind of caliper is used to draw parallel lines uh with respect to the age here you can see this particular odd leg is moving uh with the edge and if you just uh move then uh this constant distance between these two legs is maintained that means you will get a parallel line with respect to this H so that can be drawn with the help of or click caliper few more measuring and marking tools are shown here you can see this is what is called the height gauge and with the help of height gauge we can measure the height but definitely in that case this higher gauge is placed over the surface plate and surface plate is generally made of cast iron and it is generally labeled so that it is horizontal the surface becomes horizontal and then the height gauge is placed over it and you can there is a scriber you can see attached with the height gauge and you can measure a specific height from the surface plate at the angle block here you can see this is what is the annual plate and this angle plate is used to rest this particular surface at an angle 90 degree with the surface surface step so uh this angle plate the surface plate or the height gauge these are all used to for the layout work on a job as you can see and here you can see that chalk uh is used as a marking tool because initially the chart Mark is given on the surface and after that with the help of the scribers scriber attached with the height gate is used for the marking now here we can see a very very important uh measuring and working tool which is the combination set and in a combination set you can see the different parts of a combination set like it has a square head this one is what is the square head and this one is the protector head and this one is the center of it and there is one blade all the or the rule that is there and their application depending upon a particular application one of the attachment is attached with the blade and it is used here you can see in the first picture the center head is used to find out the center on a cylindrical object here you can see is Center head is actually inserted within the rule and then if you draw a line on the along the scale it will be the diameter now you just rotate the center head and you place it maybe here and the scale will at that time will be according to along this line and it will give the center in The Cutting point of the two diameter so this is the wave of the center that is used in the combination set here you can see uh this particular surface one surface of the square head is uh 90 degree and the another surface that means that this surface is at an angle 45 degree so that means the two angles ah that means 90 degree or you can check the squareness of a surface if this is an object to check the whether these two surfaces are 90 degree or not you can use this region that means uh one part will be the part of the ruler and the other part will be this surface this surface as a stock and this one will then act as a blade like a tri Square here you can see uh this 45 degree angle also can be measured okay so uh in this way square head can be used here you can see that we can also draw a line at an angle 45 degree with the help of a square head and here you can see uh here there is a scriber subscriber is actually inserted in a hole and when scriber is required that's driver is taken out from that hole and that is used for scribing or marking on a metal surface and this lock is actually used to save this blade with the square head so exactly this kind of lock bolt is there which is basically used for all the heads to attach with the scale or the root the protector here you can see since the angular marking is there you can use uh marking at any angle with the help of protector head here you can see there is a spirit level as well in the square head and the spirit level helps to check whether a particular surface is horizontal or not so here you can see uh a particular angle is set in the protector here and after that if the help of a scriber to control or you can mark the line at that particular template now let me show you a video so here you can see the different uh component of the combination set like the square head here you can see the protector gate and here it is the Center head and this one is a rule or the ruler and now to see the opposite side of the scale you can see this particular slot is there that helps to attach the different Heats into the oh no and here you can see the 45 degree marking you can do with the help of that here is the spirit level to check whether a surface is horizontal or not now you see that how the square head is inserted into the ruler and see now you can check the squareness like exactly like a try Square because this angle is 90 degree you can also check the 45 degree angle and these also uh square head also can be used to measure the depth of a surface like a depth gauge here you can see we can measure the depth of a surface next The Protector gate so exactly in a similar way protector head can be set within the blade and after that you can check the angle here you can see the angle is 90 degree so it can also be set at different angle and you can scribe line you can check the angle here as well now here you can see the center of it and with the headboard Center here you can identify the center of an object by describing here you can see the blade is set after attaching the center of it and then with the help of the scriber this line is strong and then it is rotated and another diameter is strong and in this way we can find out the center next we will see uh some more marking tool and these are like for the marking the center we use the center punch here you can see for the center point the angle in the punch that is used is 90 degree the point angle is 90 degree and there is a grip so that you can hold it and then with the help of hammer you can punch and you can see that the grip is nulled so that you so that the friction will be higher you can grip easily is generally used suppose you want to mark on a Surface in a metal surface in that case a series of dots is generally marked with the help of a hammer and the points and in that case the dot punch you can see the included angle is 60 degree so the difference between the center point and the dot point you can see the point angle is different and other than that some alphanumeric uh for different branches are there to give some impression of the letters of the numbers so these are called the letter Punjabi a number next we'll see the measuring uh surface gauge so this surface gauge is fixed type in this service days you can see that one scriber is attached and this driver having two heads uh one of the end is bent and another one is a straight so this is ah used to draw or Mark lines which is parallel to the base so generally the surface gauge is placed over the surface plate and on a particular surface with the help of the scriber you can draw a line parallel to the surface plate on which the base is there and it is also used to check the parallel surfaces with respect to another surface and in that case the wind and also used next some inspection tools these are used for checking the wire diameter you can see this one is used for different diameter wire diameter is actually marked uh actually the holes are there so whether a particular wire is fitted on that that is checked so this is called the wire gauge exactly in a similar way you can check the thread pitch speech of a particular thread and that is by a different piece pitches are there in the thread Gates here you can see the radius grid we can measure the radius and the filler gauge is used to measure the gap between two methane components so for holding tools we can use the bench wise already you know the different parts of the range wise we can use the file choice where the pipe is gold and after that to prevent fitting work can be done and the Hand devices are also used for the small walk now for the cutting we can do swine with the help of Hacksaw and you can see there is a frame attached with the hacksaw there's a hexa blade handle part is there and with the help of a start you can join the blade with the frame and uh wing nut adjuster is also there to properly tight the blade with the frame and here you can see the teeth of the blade where you can see the relief angle and the weight angle are provided and this rectangle are basically provided so that it can penetrate and for the metal work this candle is generally not very high generally up to 560 degree and here you can see this is the relief angle relief angle is provided so that the work surface is not damaged and you see the specification of the blades are done with the by uh number of tips for each and you can see that a 14 DPI teeth are used for large section of my material and for the last section of tough material you see the TPI is increased that is 18 DPI and for angle iron and heavy pipe brush copper we use 24 TPI teeth and 32 PPI used for thin tubing so as the hardness increases generally the fine teeth or the TPI intensity increased now chiseling is another cutting operation and in that you can see we use the cold chisels okay and cold chisels are the name is given because this scissors are used on the surface which is uh at the room temperature or below liquid crystallization temperature generally for the forging operation we use the hot cheese so here you can see the included angle uh at the point is a 60 degree which is called The Cutting angle of the cheese Cutting Edge you can see and this is this part of the Chisel is called the stock and this part is called the head there are different types of cheese depending on the its shape and the use uh like uh if you want to here you can see the side cut season or round nose chisel these are some special purpose scissors used for special purpose applications like for a oil passage in a machine we can use the round nose diesel for keyway cutting we may be used this kind of sidecar chisel like that next uh we can see the different filing operations or different files that are used and file can be of different kinds depending upon the cross section of the file like it can be half round it can be square file or a round file or a flat file or a triangular file or the file can be depending upon the roughness it can be of different kind like graph file or a bastard file or a smooth file in this again C file so these are depending upon the smoothness file also can be of different kind and the different parts of the file as you can see in the figure this and this this is the age of the this is what is the age this part is the age okay and this is the tip and this one is the face and the fine length here you see this length is what is the file length okay this length is the file name this is one of the specification of the file other than the parts there can be single card of the double card so there are different uh kinds of based on the surface roughness they are of different kind depending upon the cross section they are of different kinds okay next we'll see The Greening not really for creating the whole area metal piece one of the option is definitely not reading and really can be done with the help of a drilling machine here you can see the different parts of a drilling machine like there is a table there is base this part is called the column of the drilling machine electric motor is attached over there this part is called the head hand wheel is there to move the uh the drill bit along with the chop and here you can see chart where the real beat is set these are the different parts of a drilling machine now let us see that what are the different kinds of real beat this is basically the cutting tool and you see that there are two different kinds of drill bit possible one is the straight shank tree where you can see this part you know is called the shank and this shank is straight there is no paper present over there and this one is a paper sandwich where some taper is there the sand portion now how this particular drill bit is fitted in the drilling machine in case of a straight shank real uh to fit it in the drilling machine it requires a chart so this particular tool is uh hold with the help of a h drilling Chuck so here you can see the picture of the drilling chart and this one is the uh this one is the real Sharp key this one is the real Chucky with the help of this Sharp key we can lose or we can tight the jaws of the uh Chuck so here you can see uh there is a three jaw Chuck which is basically Universal chart so by adjusting a particular jaw automatically the other two are adjusted or same turned so there is no problem of centering of the real axis real bit access and here you can see in this part this particular chart there is some Hardware behind the Chuck and in the hardware there is some taper present so this Hardware is attached with the chart first and in the hardware there is more stepper cut and these most paper R Bar is now fitted within the sleeve so this particular kind of sleeve is present in the drilling machine and this particular sleeve is used to hold that more stepper so in the sleeve as well the taper is there and that particular art box goes into the sleeve and then it is connected with the drilling machine in case of a paper shown here there is no need of any drilling it shaft because since it is a depression dream so that is why it directly goes into the steel and then sleeve is attached okay and to remove the hardware from the remove the hardware or to remove the entire the paper shrunk from the sleeve there is a key that is called the drift key which is used now uh let us try to visualize the different component uh open repeat driven corporate open drill bit so here you can see uh different parts rather not component so here you can see this is uh what is the shank part and now the whole uh The Passage through which the chip can come up that particular passage spiral passage is called the flute okay and you can see some Helix angle is provided and here you can see this is the drill axis and this is what is the diameter of the real Heat now here you can see the this is basically The Cutting Edge this is called The Cutting leaf or The Cutting Edge so this is what is The Cutting Edge through which the material is cut okay and here you see this is what is the chiselage remember this season layer is not the uh doing any cutting operation okay so this is remember what is the cutting operation that you can see uh at cross-sectional view this is what is the uh cutting lip which is basically the where the cutting is taking place and margin is basically this region here you can see uh PGA which is called the margin and throughout this is and here you can see the wave this portion the central solid portion which is going throughout the there is a very small portion a small diameter where the material of that read is solid okay so that part that part is called the wave that solid part is called The Wave okay so here you can see this is what is the wave thickness so this is the solid part and the point angle here the angle which is formed is called the point angle and in case of it who is stream you can see the point angle is around 118 degree so this is important you have to remember uh it is 118 degree okay but definitely for a harder material training a very hard material in that case may be this angle may be more okay and for a softer material this drill bit angle may be lower than that regarding the material material of the real bit of can be of different kind uh in our Workshop we have the drill bit which is made of high speed steel it can be made of the carbide and different other types of real bit materials are also available next let me show you the video of a drill bit so that you can understand these different parts so here you can see the drilling operation and The Cutting fluid is continuously supplied and through the passage of the flute so the flute you can see the chip is coming out the different parts of the trail we will be explained so here you can see the float is aligned to flow The Cutting fluid and the chip can come out so here you can see the Helix angle which is provided on the deal the Helix angle can be small or large and accordingly it is called slow or spiral or the first spiral drill here you can see this part is showing is the land and the function you can understand raises the torsional strength here this region is the margin this is what is the margin you can see the margin can be more depending upon the applications or heavy operations now if you see the cross-sectionality you can understand this is the solid part which is called The Wave and wave thickness can vary and it can be parallel or a small paper is may also be there you can see the flank surfaces this is the cutting leaves for the curvature cutting chisel is remember that is not the dozen cart so it takes majority of the thrust these are the Heat or basically the design basically the plant surface of the Hill this is the point angle generally 110 degree but it can be more than that or it can be less than that depending upon the kind of materials let us not going to detail of the relief angle of other things here you can see the different fiscellage angle also being shown okay now let me show you this particular video where the arrangement has been shown that how real it is fixed into the green Chuck here you can see this is what is the green chart and here you see the real Chuck key and here you see the three Jaws are there and now you see that strip Shank real beat is fixed in the Chuck and in the help of Chucky the Jaws are adjusted or tightened and automatically the real axis is centered and after that it is required to fit into the drilling machine and that is why here you can see here you can see the R1 and Hardware having or more stable and this article is fixed the other end of the chuck and the armor is fixed and then it is inserted into the sleeve here you can see having the similar paper and now it is fixed into the breathing machine so this is the way how this is what is the drift key that is helping tool remove the hardware from this attachment and as mentioned in case of your tip or shank key there is no requirement of the Brain Check next uh reaming operation framing operation is used to create smooth hole on an existing Rim drill with the remote is the tool which is used for the ribbing operation similar to the draining but uh for the remaining operation existing pole should be there and then the operation is done definitely the surface roughness of the smoothness is better in case of a streaming if you compare with respect to drilling generally is done after uh this is the final finishing remains term after training okay actually initially the drilling is done after that if required some Boeing operation is done and then finally the dreaming is done then uh for the internal thread uh P that can be cut with the help of this operation it is called the tapping operation and for the tapping operations uh three sets of tab are used one by one this is the first one which is the paper tab and with the help of a tap range as you can see this is what is the tab bridge and then the uh part the one the tap is first fixed on the range and then with the help of this step range thread is cut on the hole okay so initially a taper thread uh taper tap is used here you can see eight to ten uh threads are different okay so if you found uh from the uh top you will find that now if you come from the bottom uh you will find that 8 to 10 threads they are paper and these are basically they're straight there is no paper in this region okay but eighth to tip uh from the bottom they are deeper so initially uh since this is a paper so initially this part goes very easily within the hole and after that this is the region where the threads are mainly cut then three to five threads uh which are paper in case of a clock so plug tap is the second uh tab in the set which is used so initially the paper tap is cut on the hole then with the help of a plug tab uh we cut the thread in the hole and here you see three to five that means we are gradually increasing the threads uh and finally in the bottoming tab is used in the step three for the finally uh and 1 to 1.5 threads so almost throughout within the whole now trade will be cut okay so this is the order how the temp set is used now uh this is very important that what should be the particular drill uh drill bit size that you need to take for that uh suppose you have to create a whole uh and it is written that it will have some uh internal thread of say in six into say one M six into one so this is basically a metric strip uh and you can see this one is the pitch one is that pitch and this is six which is used uh as the so the three major diameter this six is the major diameter major diameter so in this figure you can see which is the major diameter so here you see this diameter is the major diameter this is the major diameter and one is the pitch so Peach is basically distance between two Crest here you can see and then the real goal size will be according to this formula that is Major diameter minus P so the read hole size for this particular specification of the internal thread will be 6 minus 1 which is 5 so 5 millimeter uh real bit you have to take to create the hole next uh it is required to understand the different types of State but before that uh let us see what about the external thread how it is called you can see that external thread is cut may be cut with the help of dyeing operation and in that case the diet and diet stock is used here you can see this is what is the dry stock okay this is what is the die stock and within the dry stock this particular uh die within the die stock you see this circular die is there So within livestock the circular die is a split circular dye is placed and then you can see in this picture uh with the help of this rice top uh you can create the external thread on the job on a cylindrical job you can create this kind of external thread by rotating it so this is the technique how the external thread is created now let us see some of the thread terminologies and the different types of threads so this region which is called the crest this inclined surfaces of the flank this is what is root here you can see this is the Helix angle now the important terminologies like pitch diameter the minor and the major diameter so this is what is speech this is what is thread angle and this is thread depth now what are the different types of Shades possible we'll see first we will see the metric thread see the thread angle is 60 degree here here just you try to observe that at the crest you see the surfaces are flat and at the root it is in uh having some radials okay so it is carved so these are the things that you have to remember these are the general purpose to use these threads are used and how they are specified you can see that M8 into one one two five so that means 1.25 is basically the pitch of the threat and eight is the major diameter and M indicates it's a metric thread now each thread foreign that here the major diameter is 3 by 8 and 16 is the threads per inch so number of threads per inch that is given uh that is 16. and it is also used for the general purpose and it is similar to what you can see in case of a matrix rate and next with fourth straight to see that now both Christian root of out and included angular thread angle is 55 degree this is at method of the trapezoidal thread and you see that it's used in Machine Tools Jax aircraft modified Square thread high transmission efficiency is the main criteria remember it is also representative of the included angle is very small FDA now about twisted it can be very high load the heavy lifting transmission rates turning Milling machines it is used to be threads for locomotive Works used wrong thread it's also like the trapezoidal thread improve transmission efficiency for power transport this kind of threads are used knuckle threads here you can see blank surfaces caught next we'll see some of the finishing operations like lapping awning popping and super finishing they are the finishing operations and for the very very smooth finish finally after grinding basically this kind of a lapping or honing or superfinity uh buffing super finishing this kind of operations are done in case of a lapping operation as you can see in this picture here in this picture you can see the mapping operation where a walk piece is there and this work piece is placed over it on our lap plate this is the left plate and in the lamp plate some embedded sharp particles are already there and some slurry is used and basically some oil kind of a thing and some abrasive particles okay those are there and some rotational movement is given on the piece or some sliding movement is hidden in the work piece and this is how the mapping operation is done now coming to the honey operation uh you can see that in this picture these are the honing Stones these are onion stones and suppose this is uh some Hole uh in which you want to finish the pole with the real performing operation so in that case you can see the reciprocating motion of the onion tool is done as well as this honing tool is rotating so both basic programming and the rotating motion of the Tool uh create the surface and the this kind of across hatch pattern is created on the surface so this is what is the honing operation now coming to the buffing operation here you can see the bottling operation is done where some wind is used some lava to build or some leather or coughing wheels are used some cotton is there and over that some buffing mixture that is used and then this field is rotating you can see and some surface is police with the help of this particular mapping mixture and this process is called the buffing polishing is also similar kind of the thing in that case as well there is uh on a field uh on a leather wheel rubber bill but in that case the abrasive particles are embedded within that particular field okay it is not loose like buffing okay so that is what is the polishing operation and finally the super finishing operation is similar to the honing operation here it also can see that in the stone where the uh this Stone which is used for this super finishing operation that is having both the reciprocating motion as well as the rotating motion and the surface which you want to do the super finishing uh you will find that this kind of a marking will be there so uh to some extent this honing operation and the super finishing operations are similar the only difference is that in place of a phoning operation the stroke length is larger in place of Performing operation otherwise in case there is super finishing operation the stroke lens are smaller the speed service if you compare with respect to the owning operation the speeds of different operation is known whereas the speed of the economic population is super finishing operation is let's here also you can see that some pressure is given on the stone and then it is rotated that means it is reciprocating as well as the job is rotating so this kind of surface is prepared and these are here is a comparison that if you see that lapping operation uh honing operation you can see the surface finishing is very very high here you can see the surface finishing is very very high as you go in this direction the surface finishing is more and if you see the honing operation so this is the honing operation so it's finished yeah lapping operation surface finish is this one so that is also very good and super finishing is very high so here you can see this is the honey this is polishing this is polishing this is the honey this is lapping and this is super finishing okay so we can see the super finishing is giving the best surface finish among these three or among these four and after that it is the lapping and then it is the polishing or the buffing and after that you will see the honey so uh if we just make an order of the which one is the finer surface finish operation it is basically the super finishing then lapping then polishing and finally the honey okay now here are some videos about these operations that I can show you so so here you can see there's not even some oil and abrasives are there on the black plate and the job is given some motion along with the pressure at the head of the hand and this is what is the lapping operation here you can see some rotary motion is given on the left so different way we can do the let me show you so these are the abrasives and some oil kind of a thing it will create some slurry and then see this is the job that is fixed and then the pressure is given from the top and some rotational motion is there so this is how the lapping operation can be done next uh let me show you this one this is a honing operation as you can see here you can see the running Stones it is having abrasive sticks are there so both reciprocating and rotating motion is taking place of the morning stones coolant is also supplied so this is how the founding operation is done this is here you can see the warning tool okay [Music] next uh let me show you here you see the buffing operation and the polishing operation is done and finally we will see the super finishing operation so here you can see that roller is fixed and then so here basically some Diamond left film is passed through the roller and if you see that both reciprocating motion as well as the rotary motion is going on which is providing this kind of vibratory reciprocating motion oscillatory motion and the rotational motion is going on this is what is The Superficial operation thank you