Good morning friends. In today's lecture, let us learn about investment casting process. Investment casting process was a very ancient process. Now, why should we learn it today? Or why investment casting process? The reasons are many. What are they? Investment casting can produce very thin and most complex features. If we want to produce very thin sections say of the order say 0.75 mm or in the cases where extremely complex features have to be produced, then investment casting is the only solution. Next reason, it offers excellent surface finish. Investment castings do not give us very good surface finish. We have to machine it to obtain a good surface finish, whereas investment casting offers us excellent surface finish. Most of the times, no machining is required or minimum machining is required. Next reason, it offers excellent dimensional accuracy means the difference between the size of the pattern and the size of the casting is almost 0. So, it offers the excellent dimensional accuracy. Next one, it can be used to cast all the metals and alloys. Now, let us see this. How it can be used to cast all the metals and alloys? If we see in this table, we can see alloys covered in investment casting process. So, here we can see along with this, we can also see alloys covered in the other casting process and other manufacturing process. And if we see, say here these are all the different to what say casting and manufacturing process and here these are all the different to what say cast alloys and other alloys which can be manufactured by different casting process or manufacturing process. If we see the die casting process, we see ductile iron cannot be cast using die casting. Whereas, tool steel also cannot be cast, steel cannot be cast, stainless steel it cannot be cast. Only aluminum, magnesium, copper, brass and bronze alloys can be cast using die casting process. What about titanium alloys, super alloys? Those also cannot be cast using die casting process. And if we see this forging, it is a one of the important manufacturing process. Ductile iron cannot be forged. You see here, whereas, tool steel, steel, stainless steel, aluminum and magnesium alloys, copper and what say bronze and brass, titanium alloys, super alloys can be forged, but ductile iron cannot be forged. Now, this is another process that is the powder metallurgy process. In this, we can see ductile iron cannot be done, produced using powder metallurgy. Whereas, tool steel, steel, stainless steel and titanium alloys can be produced, parts can be produced using powder metallurgy. Now, let us come to the sand casting process. In this process, yes ductile iron parts can be produced, tool steel parts can be produced, steel parts can be produced, stainless steel parts can be produced and aluminum, magnesium, copper, bronze, brass alloys can be produced using sand casting process. Whereas, titanium alloys cannot be produced using sand casting process. Whereas, again super alloys can be produced. Now, let us see the another manufacturing process that is the weldments. Now, here we can produce only steel, stainless steel, aluminum, magnesium, copper, bronze alloys, titanium alloys and super alloys. In this welding ductile iron and tool steels cannot be welded. Now, let us consider the topic of our interest that is the investment casting. Now, in the investment casting, you see ductile iron can be cast, tool steel can be cast, steel can be cast, stainless steel can be cast, aluminum, magnesium alloys can be cast, copper, bronze, brass alloys can be cast, titanium alloys can be cast and finally, super alloys also can be cast. Virtually, all the metals and alloys can be cast using investment casting process. So, these are the special features of investment casting process. So, among all the what is a casting process and manufacturing process, investment casting gains this unique what is the importance that every alloy and every metal can be cast using investment casting process. Now, before going to this subject, let us see the history of investment casting process. The principles can be traced back to 5000 BC when the early man employed this method to produce rudimentary tools. So, this method was in practice even 5000 BC by the ancient man to produce the rudimentary tools. So, those days if a war has to takes place on both sides there will be two groups will be there and they will be throwing the spears. So, these are the spears. So, this is the metallic what is a cast component and here there will be a wooden what is a handle will be there. So, they will be holding the spear and they will be throwing to the other group. So, this is how they used to do the wars those days. Now, these spearheads were manufactured by the ancient man using the investment casting process. How initially the ancient man has made wax models of the spearheads, you can see here. So, this is the one wax model for one spearhead. So, this is another wax model for another spearhead and this is another model for another spearhead. So, these three were joined together now there is a central tree was there. So, now again these are all joined here and here also we can see another vertical projection. So, this entire structure entire assembly is made up of wax. Now, the next step done by the ancient man was he has compacted the sand sticking sand around the this pattern wax assembly. You can see here he has compacted the what is a sticking sand and it was dried. Now, after that he has what is a heated this system hand moulding system then what happened. So, this because of the heat produced this wax pattern would melt and it used to drain out and inside there will be a cavity and whose shape is similar to this wax assembly or the pattern. Now, he has melted the metal and he was pouring into this cavity you can see here is pouring is done.  So, there is another hole here. So, it would raise through this hole. So, then he will be realizing that the cavity is filled with the molten metal and he would stop pouring the molten metal. Now, after some time the molten metal solidifies inside the sand mould. Then he was breaking the sand mould you see now after the sand mould is broken it was looking like this. Now, so these are the this is the structure or the assembly of the three spearheads.  So, this is how the ancient man has produced the spearheads using the investment casting process. So, we can conclude that what is the investment casting is the most ancient process used by the ancient man. Now, we can see some more history. So, later this process was used for making art castings for several centuries. So, here we can see the bronze what is a status of what is a important personalities and the kings. So, these what is a bronze statues were made by investment casting means initially they used to make the what is a face or the face of that personality by wax model. They used to create a wax model around that they would make a what is a sand mould. They used to compact the sand mould and they used to heat that what is a sand mould and the wax would drain out and then they would pour the molten bronze. Now, here we can see these are the again art castings bronze castings. So, these are made by investment casting process. Now, let us see the developments in India. In India again this process was in use even during 2500 BC. So, those days a dancing girl was made you can see here. So, this is the what is a dancing girl bronze girl. So, this dancing girl became very popular those days because this girl has several what is a statue has got several artistic features. All these artistic features were excellently cast using the investment casting process means initially they made a wax model of this dancing girl then they kept it inside a sand mould. They compacted sand around this wax model. They heated it then the wax has drained out then they poured the molten bronze into that mould. So, this is this bronzing what is a dancing girl is still in there in Mohanjadwara. So, now it is in Pakistan. Now, again we continue the history. The first scientific use was in the year 1897 for making dental crowns. Here we can see. So, this is the dental crown again this dental crown was manufactured and it is still manufactured using the investment casting process. Now, the technology had a great evolution in the United States during the world war second world war. Now, there was a great need for making precision components with complex geometry such as turbine blades for aircraft's engines and so on. So, here we can see these are the turbine blades and they have very complex what is a geometry and these are manufactured by investment casting process. With excellent surface finish and with excellent dimensional accuracy we are able to get these complex featured cast components. Now, let us see the development. So, far we have seen the what is a history in what is a nutshell. Now, let us see the developments during the 20th century. What are the developments? So, these are the what is a different what is a phases of the developments of the investment casting process. The first is the solid mould or block mould investment casting. Next one plaster mould investment casting. Next one mercast process and the next one searmixial investment casting process. Now, let us see all these one by one. First let us see the solid mould or the block mould investment casting process. Now, in fact this is the what is a what is a principle used by the ancient man. What the ancient man has done to produce the what is a spearheads initially he made a wax model of the spearheads then he compacted what is a moulding sand around this wax model and he heated that then it got drained then he poured the molten metal into that mould. So, solid mould what is or block mould investment casting is same as the method used by the ancient man to produce the spearheads. Now, here we can see so these are all the jewellery components several jewellery components we can see rings. So, several such rings are what say wax patterns are assembled together here you can see. So, this is the assembly of the wax pattern for several rings jewellery rings. So, several such patterns are assembled here you can see here. So, this is the central tree. Now, around which say they used to make a ceramics slurry. So, the ceramics slurry this is kept inside a what is a flask. Now, the ceramics slurry they used to pour inside. So, that the ceramics slurry would fill the entire flask and the ceramics slurry would go around each and every pattern and it used to take the shape of the extreme what is a fine details. Then in such a state the ceramics slurry would be dried out. After the ceramics slurry is dried out then they used to heat this system then what will happen the wax would melt and it used to drain out then they will pour the molten metal into the mould. Then after solidification they would break that mould then finally they get a casting like this. So, this is the solid mould or block mould investment casting process. Now, what are the advantages of solid mould or block mould investment casting process? One is mould is very strong why because around the patterns we are what is a completely filling the ceramics slurry inside the flask. So, the mould is very strong. Next one the process is simple. Next one what are the disadvantages of this process? Poor permeability everywhere there is what is a ceramic slurry is filled. So, during what is a pouring of the molten metal if some air or hot gases are trapped it is very difficult for the hot gases to escape from the mould because everywhere the ceramic slurry is filled. Next one large consumption of ceramic slurry everywhere we are filling. So, that way we have to consume lot of ceramic slurry. So, that increases the cost of production. Next one longer setting time. So, once we pour the ceramic slurry around the what is a assembly of patterns inside the flask. So, that would take several hours for setting. After that we have to dry it again after that we have to drain the wax. So, that way the what is a lead time will be increasing abnormally. So, that increases the cost of production as well. So, these are the advantages and disadvantages of block mould or the solid mould investment casting process. Next one. So, we have completed this one solid mould investment casting process. Now, let us see the plaster mould investment casting process. The wax pattern is placed in a flask and the plaster of paris is pulled over the pattern. So, the process is similar to the first one the solid block investment casting process. It is similar and plaster moulding investment casting process is similar to the solid mould investment casting process. The one difference is instead of the ceramic slurry plaster of paris is pulled over the pattern. So, that is the difference. The unity is shaken so that the plaster penetrates into every small detail of the pattern. The system will be shaken so that plaster of paris will be going all around the extreme details fine details of the pattern. Now, after sometime it will be set and it will be hardened. The wax pattern is drained out by heating. Again same thing. Then the mould is then cured in an oven to remove moisture before molten metal is poured. Sometimes some moisture will be present. So, this moisture is to be removed. So, before pouring we need to heat the what say this mould plaster mould. Now, then we pour the molten metal after the metal has solidified the plaster is broken from the cast part and the casting is taken out. So, these are the advantages. The process gives very good surface finish because plaster of paris is a very what say fine slurry. So, because of that even the casting will have a very fine surface finish. The process also offers good geometrical accuracy. So, these are the advantages of plaster mould investment casting process. Now, these are the disadvantages. Used plaster cannot be reused. So, this plaster itself is not cheap. This is expensive. Now, when we have used this what say costly plaster the drawback is it can be used only once. Once it is used once we break that what say plaster after solidification it cannot be reused. Its cooling time is considerably longer and hence it takes longer time for setting. So, that is how large castings cannot be made using this process. It can be used only for small castings and medium size castings. Next it can only be used for alloys with lower melting temperatures such as aluminum, copper, magnesium and zinc. We cannot produce castings of higher melting temperatures. So, that is another limitation. So, this is the typical plaster investment mould. We can see here yes this is a what say cylindrical flask and here inside we can see plaster. Plaster failure is we can see and after sometime it would be hardening then they used to what say melt the wax and they used to drain out the wax. Next one mercast process that is the third process which was used in the investment casting process. What is this mercast process? In the mercast process solid mercury is used as the pattern material. Generally wax is used as the pattern material in investment casting process. In fact in the first two processes we have discussed wax was used as the pattern material, but here the solidified mercury is used as the pattern material. So, that is the unique feature of the mercast process even the name implies the same mercast means mercury is used in this casting process. Now then after that initially we have to make the mercury pattern solid mercury pattern. Then what is the next step? Ceramic shell is made around the mercury pattern by repeatedly applying ceramix lary and stucco. There will be a fine ceramix lary will be there. So, this will be in fact the solid what say mercury pattern will be dipped inside the ceramix lary and it will be taken out. Then stucco will be sprinkled over the pattern and then it will be dried. Again the pattern will be dipped inside the ceramix lary it will be taken out. Then fine stucco will be sprinkled around the pattern. Likewise what say dipping inside the ceramix lary applying this stucco and drying. So, this cycle goes on for at least 5 times 5 to 6 times. Then a ceramic shell is created around the what say mercury pattern. Now after the shell is hardened mercury is drained out by raising its temperature. At room temperature one must remember that mercury will be in liquid state. Now this what say making the ceramix shell around the mercury pattern is done below the room temperature. Now once the shell is created now the temperature will be raised. Now mercury is drained out by raising its temperature followed by pouring of the molten metal. Once we raise the temperature or at least when we bring it to the room temperature the mercury will be melting and it will be drained out from the shell. Then we can pour the molten metal into the shell. So, this is how the mercury process is carried out. What are the drawbacks of this process? Mercury patterns are very heavy. Next one pattern production and shell building had to be done at temperatures below minus 39 degree centigrade. So, at this temperature the mercury would be in solid state. The melting what say temperature of the mercury process becomes difficult and expensive means we have to create that what say environment. We have to control the temperature of the working area. We have to create such a temperature where the temperature will be maintained below minus 39 degree centigrade. At such temperature only mercury will be in solid state. So, the entire process right dipping the mercury pattern into the ceramic shell are taking out sprinkling the what say stucco drying it again dipping into the ceramic shell area. The whole process has to be carried out below minus 39 degree centigrade. So, that way the process becomes expensive. Not only that the mercury pattern itself is costly mercury itself is costly that way the whole process becomes costly. So, nowadays this process this mercast process is no more in use. Next one is the ceramic shell investment casting process. So, this is the what say ceramic shell investment casting process and this has been developed in the recent years and it has gained popularity and it is in use all over the world today. Now, what is this a ceramic shell investment casting process? It is similar to mercast process. In the mercast process what we are doing we are making a mercury pattern and we are what say making a solid mercury pattern that pattern we are dipping inside a ceramic slurry taking out and sprinkling stucco drying it again dipping inside the what say ceramic slurry take out sprinkle stucco dry it like that we used to do 5-6 times. The same way we used to do in the ceramic shell investment casting also, but where is the difference? Here in the case of the mercast process mercury is the pattern material, but here in the ceramic shell investment casting process wax is the pattern material. However, wax is used for making the pattern instead of mercury. Now, here we can see a case study manufacture of a turbine charger rotor. So, here we can see this is a turbine charger rotor and here we can see this is the what say blades of that rotor this one. So, this what say rotor it is manufactured by ceramic shell investment casting process. How? Initially a wax pattern of the rotor is made you see this is the wax pattern. Now, after making this wax pattern it will be dipped inside a ceramic slurry fine ceramic slurry then it will be taken out stucco will be sprinkled around that it will be dried again it will be dipped inside ceramic slurry stucco will be sprinkled over that and it will be dried again it will be dipped in the ceramic slurry likewise 5-6 times it will be dipped in the ceramic slurry and stucco will be applied and it will be dried, but one must remember that in the beginning that generally there will they used to take two types of ceramic slurries. In the beginning there will be a fine slurry will be there as maybe after 3 or 4 coating there will be coarse slurry will be there. So, first three course it will be dipped inside the fine ceramic slurry after third coating there will be a coarse slurry will be there. So, and even the stucco will be coarse urban. So, that as we going what say to the outwards the permeability of the shell will be increasing. So, here we make the ceramic shell in this way by dipping into the what say ceramic slurry and applying this stucco finally you see a shell is created then we heat it the wax pattern inside the shell will be melting and it will be drained out then molten metal will be poured into this shell after solidification we can break that shell finally we are getting the turbocharger rotor you see. So, this is the shape of the pattern wax pattern and this is the final metallic what say part we are getting. So, this is the simple principle of the ceramic shell investment casting process. Now, let us see the advantages applications and limitations of investment casting process. The size of castings can vary from few grams like dental brace for a tooth or to about 500 cases complex aircraft engine parts we can make very small castings like jewelry components or a dental brace and their weight will be few grams we can make by investment casting process whereas the complex what say aircraft engine it weighs about 500 cases that also we can make using investment casting process. Now, second benefit advantage is the excellent surface finish of the order 1.5 to 3.2 microns RA is generally obtained very good surface finish excellent surface finish can be obtained using the investment casting process. Next one close dimensional tolerance is obtained you see the order 0.08 to 0.13 mm per 25 mm size of the part such a close dimensional accuracy can be obtained using investment casting process. Next one typical minimum wall thickness of 1.5 mm with thinner sections of 1 mm is also possible. In the casting what is the difficulty say if we want to produce thin sections it would be very difficult especially in the case of the sand casting process but in the investment casting process even if the thickness of the section is 1 mm we can successfully cast that component. So, that is another benefit of investment casting process. Next one very fine details can be produced in small castings like jewelry castings very very fine details which may not be possible with other casting process can be possible using the investment casting process. Next one complex shapes can be made sometimes we come across certain castings there will be so many complex features especially in the case of the jewelry ornaments. Now such complex shapes can be produced only by investment casting and not by any other casting process. No or negligible finishing operations are needed sometimes no finishing no machining is required after the part is produced sometimes minimum machining is required. Next one any alloy can be cast that we have seen in the beginning itself any alloy can be cast which is not possible with other casting process including ones that are impossible to forge or too difficult to machine any hard alloy any soft alloy can be produced using investment casting process. Next one castings are free from usual defects that are encountered in sand casting process. In the sand casting process we used to get several defects like what say blow holes cracks. So, these kind of defects won't arise in the case of the investment casting process. So, these are the advantages of investment casting process. Now these are the general applications of investment casting process art castings and jewelry castings the ancient applications of the investment casting process is it is still going on art castings and jewelry castings are still produced using the investment casting process. Today its applications are found in all branches of both general and specialized engineering. In general castings we can produce and in the specialized engineering like turbine blades rotors we can produce using investment casting process. Relatively simple levers and ratchets to impeller wheels for diesel turbo charges very simple levers can be produced and also very complex parts like diesel turbo charges also can be produced using investment casting process. Next one extremely complex thin walled electronic chases components and medical hardware including surgical implants dental crowns can be produced. So, this is another unique feature of investment casting process extremely complex details can be produced. Now here we can see some applications of investment casting process. So, these are the turbine blades this is the turbine blade and this is the rotor of the turbocharger and these are produced by investment casting process and some more examples pump and valve components. We can see here they have excellent surface finish and they have several complex features all these are produced using investment casting process and here we can see these are the medical implants. So, these are the titanium cast parts. Nowadays these what say titanium cast parts are used in the surgery. So, these implants are made by investment casting process. Now these are the jewelry what say components. So, these jewelry cast components are produced by investment casting process. Now here we can see these are several tiny and precision components. So, these are also made by investment casting process. Now let us see we have so far we have seen the advantages and limitations of investment casting process. Now let us see the advantages and applications we have seen. Now let us see the limitations of investment casting process. Production of wax patterns makes the process costly wax itself is costly. Now that wax has to be blended with several waxes. Some fillers have to be mixed then we have to melt them. Sometimes some shrinkage defect used to come in the wax pattern. So, we need to reject it which is lot of care one has to produce the wax pattern. So, production of wax patterns make the process costly. Next one huge castings cannot be made. See in the case of the sand casting process even 5 tons casting can be made, but here today the limit is 500 kgs. Beyond 500 kgs it may not be possible using investment casting process. Now the process is relatively slow. Why it is slow? In the case of the sand casting process what will happen? Initially we make a metallic pattern or wooden pattern. So, the same pattern we can use for several castings and yes bring the pattern put it inside the molding box and dump the molding sand and there will be molding machines will be there and those molding machines will make the mold within few minutes and if the molten metal is ready and we can pour the molten metal. So, making a casting using what say greens and casting process is not so much time consuming. Whereas in this process lot of time is consumed. The process is relatively slow. Initially we have to make the wax patterns. We have to make the wax blends 2 or 3 waxes along with the fillers we have to make that is the blend that we have to melt under careful environment then we have to make the pattern wax pattern. Remember one wax pattern can produce only one part. For each pattern we have to produce one wax pattern. Now what is the next step? Then we have to make the ceramic slurry. This wax pattern has to be dipped inside the ceramic slurry then take out and apply the stucco and let it dry. Again dip it inside the ceramic slurry take out apply the stucco. Again dip then we will go to the next what say chamber where coarser slurry is present dip inside the coarser slurry take out apply coarser stucco likewise 5-6 times we have to dip and apply the stucco and dry that way the process takes lot of time. Ceramic slurry has to be prepared 2 to 3 days it has to be what say mixed inside a investment mixture then say 5-6 times we have to dip how much time it takes each time it has to dry for about 1 hour means what say making the ceramic slurry itself takes say 7 to 8 hours then we have to melt it and we have to drain the wax then we have to fire the shell finally we can pour the molten metal. That way the process is relatively slow compared to other casting process on the other hand die casting process means within no time we get the casting within few seconds also we get the casting but investment casting takes several hours produce one part next one incorporating the course is difficult in this process. Now we will go for the so far we have seen that the investment casting has been developed in 4 what say stages one is the solid block investment casting process, second one is the what say plaster mould investment casting process, third one is the mercast process and the fourth one is the ceramic shell investment casting process. Now let us study this fourth one in detail ceramic shell investment casting process. Now major steps involved in ceramic shell investment casting process so these are the several steps involving in this ceramic shell process that is how the process becomes longer it takes lot of time. What is the first step? Wax injection, second one pattern assembly, third step shell building, next one de-waxing, next one casting, next one knockout, next one cut off, next one finishing and secondary operations. So these are the several steps involved in the investment casting process. Now we will see all these steps one by one first one let us say the wax injection. Now you can see here this is the wax injector pattern is prepared by injecting molten wax along with resins fillers and write resins into a metallic dye. So this is the what say wax injector and here there will be two metallic dyes will be there. So these are the detachable dyes as per our requirement we can change these dyes. So when we close these two dyes the inside there will be a cavity means these dyes similar to the die casting process.  So when we close these two dyes inside there will be a cavity and that cavity resembles the cast component which we are going to produce. So this what say two dyes will be closed and wax will be injected into these dyes and it will be taken out it will be cooled down and it will be taken out. So that is the first step first we produce the wax patterns. Now a pattern wax is normally modified and blended with other waxes and materials such as plastics, resins, fillers, anti-oxidants and dyes in order to improve its properties. So normally a single wax is not used for making the pattern because no single wax possess the what say all the properties. For example what say paraffin wax is there it is soft but its fluidity is very good. So we take the advantage of the fluidity but it is very soft we have to improve its what say hardness. We mix some other wax so that it would become hard. So we also mix the what say fillers and dyes to improve the properties of the wax pattern. Generally 2-3 waxes will be mixed in certain proportions along with the certain fillers so that it will develop required fluidity, required hardness and minimum what say shrinkage. Typical proportion of the wax plants you can see here waxes will be 30 to 70 percent, resins will be 2 to 60 percent, fillers up to 20 percent and other it is up to 5 percent. So this is the typical proportion of the wax plants. So one must remember that a single wax is never used to produce the wax pattern. Always a blend made up of several components like waxes, resins, fillers and it is used to make the pattern. So these are the common waxes used for pattern preparation. One is the paraffin wax the most widely used wax, next one the micro crystalline wax, next candelilla wax, next one carnival wax, next one bees wax, next one fissure trop wax, next one finally bozocharite wax. So these are the what say waxes which are commonly used and we make a blend out of these waxes. So let us let little about these waxes first one is the paraffin wax. It is a white or colorless soft solid derived from petroleum, coal or shale that consists of a mixture of hydrocarbon molecules. So paraffin wax is white in color and it looks like this. So it is a what say petroleum product. Second one is the micro crystalline wax. It is a type of wax produced by de-oiling petroleum during the petroleum refining process. So this is a byproduct of petroleum. So this is the micro crystalline wax. Next one candelilla wax. Candelilla wax is a wax derived from the leaves of the small candelilla shrub native to northern Mexico and the southwestern United States. So this is obtained from the candelilla shrub leaves, next one carnival wax. It is obtained from the leaves of the carnival palm in the northeastern Brazilian states. Carnival wax color is different you can see here. So somewhat brown color and it is somewhat hard compared to the paraffin wax. Next one beeswax. Beeswax is a yellow to brown color natural wax secreted by honey bees to build honey combs. So to we all know the honey combs. So to make the honey combs so these beeswax they will go and what say make the honey combs. So this honey combs is made by the beeswax. So this beeswax is what say a secretion coming out of the beeswax. So this secretion will be a wax it becomes a wax. Next one fissure tropes wax. So these waxes are synthetic hydrocarbon waxes. Though they resemble paraffin waxes they are hard and have higher melting points. So color wise it looks like paraffin wax but paraffin wax is very soft but whereas this wax is hard. Next one ozocharite wax. Ozocharite wax is referred to as earth wax or earth wax which is a naturally occurring water ferrous mineral wax found in many localities. So it is its appearance is somewhat different from the previous ones. So its color is black. So these are the common fillers mixed with the pattern wax. So when we are making a wax pattern we take 2 or 3 waxes and we make a blend. Along with 2-3 waxes we also mix certain fillers. So these are the common fillers mixed with the pattern waxes. One is the spherical poly strain. Second one is hollow carbon micro spears. Next one spherical particles of the thermosetting plastic. Fillers have high melting points and are insoluble in the base wax. Hence they contribute to reduced solidification shrinkage of the mixture. So most of the times when we produce a pattern say we inject the liquid wax into the dyes. So there is a cavity between the 2 dyes we inject the liquid wax. So liquid wax there it solidifies inside the metallic dyes. Now during this solidification generally sometimes a shrinkage cavity will arise in which case that pattern wax pattern is of no use again we have to melt it. So because we are adding these fillers what will happen when we add these fillers there will be lesser shrinkage. So to reduce the shrinkage we will be mixing the fillers. Friends we will continue this in the next lecture. Thank you.


and hippie hacker, you can join us for this journey. We're gonna talk a bit about the Kubernetes, particularly the journey we've been on together and how we're almost there. Some of our story starts in another community that I was a part of. Chef, I met some really interesting people at Chef. Adam Jacobs himself and Noah Penoitz, code ranger. Very unique and interesting people. Adam's very metal and code ranger is very community. They share some DNA around culture being super important. I joke that the revolution will not be televised. It'll be coded, not necessarily with Chef, but with all of the culture that operational code can bring. Crier's a place for us to chat about such things. And the hashtag here in front of Chef is for an IRC channel, which is where we used to internet really chat before things like Twitter were around. And there's a really good story about someone who came to our IRC chat wanting to impress their significant other with some cool food that they would prepare at home. And I loved how Noah came forward and included them and said, absolutely, we'll give you a hand. And that impressed me. And I carry that culture forward with me. And I think I also see remnants of that in the Kubernetes community. Thank you for Noah for bringing that forward and thank you for Adam for setting up a company where culture was so important. While I was working there, I got to work. At some really cool places that need some really cool people. One of them included working on boats, bigger boats, really big boats, cruise ship boats. And I got to work with a couple of people to help them deploy the cloud onto said boats. It was Aaron Crickenburger and Bob Wise. Onto these ships, be a satellite while they were at sea. We would deploy the cloud onto the hardware itself, which I found really fun and really interesting. And I thought about that for a while and I really enjoyed my time working with Bob and Aaron. There were things that were difficult about that time. One was that containerization was just coming into play. Salmon hikes and friends were iterating so fast and it made it hard to develop solutions on top of this technology. We needed it. Docker on the ships at sea. But we also needed a way to orchestrate that. I'm not sure if some of our friends at Google came into play and in their spare time, 20% time, I think they came up with Kubernetes and that helped to orchestrate beyond just having container engine that ecosystem that developed into something that was beginning to kind of coalesce into something extremely, extremely valuable to all of us. Now, we've got Kubernetes and we've got Docker. I realize that I'd like to play with that. So I began working with some of my friends and there are some servers given to us by Bob, same ones we deployed at sea. And so I worked with some friends of mine and we created a co-op. That's the Vulp cooperative. So it was myself and Lucina, Taylor and LaValle and a few others, but these were the core folks I spent my time with at Vulp. And we did some pretty cool stuff together. I've known Taylor for, well, since college we're a good old college buddies. And I ended up going back to New Zealand and tried to bring the servers with me, but I did not have the funds. It was quite expensive to get the servers over there. So I reached out to my friend, Bob. I said, hey, Bob. Bob said, hey, hippie. Said, can you help me get these servers over there? Said, no, but I know someone who I'd like to introduce you to. Said, I want you to meet Dan. Dan was working on a new Linux foundation thing called the Cloud Data Compute Foundation. And he said, I think hippie can help you with that. And I really thank you for the introduction, Bob. Dan was a real visionary. And he was thinking about how can we in this initial state just demonstrate what the cloud is? He worked on demo, cncf slash demo on GitHub. And slowly that evolved into things like cncf.ci, which my friends at Volk worked on as well. And when I was back in New Zealand, oh, down here. I found that a cooperative in New Zealand to kind of parallel the cooperative in the States. That's where I was born. And this cooperative ended up founding it with Denver Williams. As a teenager, he travels from New Zealand to Berlin to speak on Kubernetes. And he has since joined Volk and I'm super proud of it. cncf.ci has since been taken over by the Volk team. And between Volk and I, we do a lot of the strategic initiatives for cncf. This focus for this talk is all about certified Kubernetes. And last time I was in China, I brought a friend from New Zealand with me. Her name was Indigo Phillips. Now, Indy brought her culture with her on that journey. And she shared with us her pepihá.  And there's another special protocol of introduction that she shared with us called the facapapa, which is the lineage of ancestors from that boat or that waka that first landed in New Zealand. And it's part of that protocol and that introspection of sharing the identity of who she is, Indigo Phillips, age 42, New Zealand Maori. Currently at that time, speaking at KubeCon, trialing to Shanghai and sharing her culture with the tech world. And the sources, the locations she's from are from Todanga Bay of Plenial, Thiruwa, where we're broadcasting from today. And Rotirua, which is about an hour from here, a lovely place, and there's a lot of parallels in that introduction that we suggested that maybe we do in our software world as well, where our software might say, here's my version, I'm currently talking to an API server, and here's the things I'm doing at this moment. The source and locations being functions inside of our code repositories to identify looking at the history, who would be best to talk to to help define what it is that we wanna test. Thank you so much, Indigo, for sharing your culture with us and influencing how Kubernetes is defined. Now, in order for us to have Kubernetes agreed on and defined by us as a community, we need to have people who can take a look at it first and say, that looks good to me. And we need people who can go through and approve it fully and say I am authority in this area, we can approve it. So I'm gonna add in a few of those people real quick. Hold on, Dems, Liget, Tim Hocken, and these were some of our LGTMers that said this looks good to me. So we'll put them here within our list of people who helped define what Kubernetes is as an LGTMer. And in addition, we had John Billomaric, Smarter Clayton, and Tim Hickson-Claire that were part of the approvers for a long time. And I'm super thankful that we got their slash approve on many of these changes. Those changes were made in part, if not mainly by our team at IEI. And I have them right here. Rion, Lionhounds, Caleb Woodbine, Steven Haywood, and Zach Mandel. So that we have all of these faces that are part of that wild journey that I've got to spend some time with and help define what Kubernetes is. One thing we noted early on in that journey is that Ken Michi showed up to one of the meetings, I believe one of the TOC meetings, and he's like, it's a governing board meeting. He said, do you know that we don't actually have tests for around 10 to 11% of Kubernetes? We were kind of in shock that that was true. And we looked and sure enough, he was right. So Dan said, let's do something about that. And so Dan shared a picture of his hard drive. This is actually a picture of Dan Kahn's hard drive with some software that scans the folders. He said, can we do something that might let us look at the Kubernetes API that might look something like this. And Rowan and some other friends at II were able to put together an image that looks like this. Very similar to Dan's vision or image of his hard drive called the starburst chart. And you'll notice that the end of the bar there's plenty of space in between and this is actually untested areas. And so at this point, when we finally got a graph together only 14% was conformance tested, which is pretty wild thinking that we all of our applications globally, all of our kube apps only had a solid surface area of about 15% to work with. But over time, we began to fill in those blanks. You can see here that they got a bit better over time. But this is for every possible API. And with our SIG architecture meetings and the people who can improve those APIs, we slimmed it down to focus just on the APIs that were required for everybody. And that means the stuff not within the red or the blue but only the green. So these are the APIs as they've evolved. Here was a 36% of just the stuff available to be tested slowly filling it in here over time here until we get to our most recent one. And this is what's looking really, really great. You see the amount of progress we've made and how very few items remain to fill in. And I'm super thankful that we are gonna get there this year. This is the year that we wipe out all of that technical debt. We can see that journey most clearly in our up into the right graph with all the release numbers here at the bottom. I'm really digging that we haven't had any more orange which was technical debt getting added. And we haven't had any regression. So that means that this is continually getting smaller and at this rate we'll be done within the next two to three releases. And that is very exciting to me. So by Q2, Q3, somewhere in there we should be pretty far along with squashing all of these out of the way. That is something I'm super excited and I know Dan would be happy to see. This is new endpoints I believe for 118. And they got introduced without tests and this is part of the gates that we have in place. And those gates are put in place not only for new APIs coming through but for new people submitting their tests. So it's been lovely to see tooling like Heptio Sonoboy being used to help people easily submit conformance results and collect them. But they are filtered through Robert and I have to move out of the way for a second. We'll help them up here through Robert Kilties, Rob Kilties and Furno Klein Hans's software that runs in Prow for helping Taylor Wagoner defend the certification. So if companies submissions run with Heptio Sonoboy get passed the gates defined by Rob and Furno then Taylor will give them the final approval and they'll have certified Kubernetes. So I hope you've enjoyed this journey and I want to thank each of you for your eyes and I want to do kind of a moment to remember Dan and Kurt Kahn, it was his vision and belief in each of us that inspired this program to come to being and I look forward to seeing this come to full fruition and erasing all of that debt. I'll see each of you face to face some day and eye to eye. Peace.


sup what is up everybody welcome back to another video and the second Q&A video of the day very questionable decision coming up here but I hope it was worth it if this doesn't remind you of hills have eyes I don't know what will a couple more steps see at the top okay welcome to Q&A video number two let's get on to it I must be completely honest when not actually completely at the top I just said completely well three times now I don't know if you can see in the distance but there is a little flagpole up there that is the true top so that's exactly where we're gonna head and I'll see you there to complete this question and answer part two thanks for being here guys I really fucking appreciate it a bit off a little more than I could chew there when I was cutting for my first physique show I was doing this three four times a week I always knew I wasn't bringing cameras along but I always knew you know when whenever I started on this walk as long as I made it to the top and back that's probably a good thousand calories burnt and you know especially if I did it faster which I have done this morning that's just fat loss mate straight fat loss it's good shit but I'll see it top I'm not quite sure I'm not quite sure how red my face is in fact let me check that oh yeah kind of red but here we are man right the top the top of the mountain and it's picturesque views the whole way around I'll show you and I'm the absolute only one up here guys which doesn't happen too often the only one it's just me I'll swing this round because well actually no you can't really see it that way but this way you can see the entire range going way way off into the distance the mac denille ranges so if I move my big head behind me that is where they continue and see if I can zoom in so here we are on top of Mount Gillan in the Northern Territory those are the mac denille ranges and my name is Jacob McDonald let's get into the questions fuck I almost forgot am I gonna sit myself down somewhere yeah I'm gonna sit myself right there this is like meditation holy fuck look look down I just looked down then it didn't didn't do me any favors have a look that's a pretty sheer rock face in fact let me see no I'm not gonna put the camera down there fuck that let's get off let's get off and sit on sit on something a little closer to the ground and try not to break your phone in the process okay all right now whenever let's do this the last question was favorite thing to do in my spare time okay next question who is your favorite player in football and basketball and rugby who is my favorite player in football you know it's hard to go past AB just because of his personality and his laid-backness and his epic social media shots but I would have to say my favorite player right now my the player I'm most excited to see play is a cross between Leonard Fournette and Saquon Barclay who's my favorite basketball player Stephen Adams big Kiwi who's my favorite rugby player honestly I could not say I wouldn't even want to say it'd be disrespectful to all of the legends I've absolutely loved throughout my childhood but look you can't go past the outside the outside backs for the All Blacks in the late 90s early 2000s which was Jeff Wilson on the right wing number 14 Joe Nolomu on the left wing number 11 and Christian Cullen at the back number 15 height and waist size I am 185 centimeters tall that is six foot one and my waist is around about 34 inches which team do you think would go see which team do you think you would go see play for your first NFL game experience I would say either Jacksonville, Kansas or either of the New York teams but I couldn't say honestly I'd like to go to any game seriously what are your goals for your YouTube page to stay true to myself first and foremost and to continue to grow it to continue to entertain to continue to inspire motivate that kind of thing as far as numbers as far as creating a full-time income through YouTube no that's not that that's not the goal that's not because it most likely won't happen best Eunice in the NFL you best best Eunice in the NFL best uniforms in the NFL I would say I fucking love the Miami Dolphins uniform I really do I love that teal and orange but in saying that I love the color red so I'd have to say Kansas City Chiefs and also in saying that you know the Jacksonville Jaguars yeah and from there I mean that's that's just because it sort of reminds me of sort of like a retro colorway but yeah I'd say anything anything I'm gonna I'm gonna stick with that Miami Dolphin okay have you been to the United States to watch an NFL game no I have not been to the United States I have only been to New Zealand where I was born Australia where I live Bali and Thailand will you give my channel some support will you give my channel some support support your boy sports and more with the madman that is not a question you mean to ask questions but if you do want to check out one of my subscribers who's taken some inspiration and motivation from me and set up his own YouTube channel which I've actually heard you know quite a quite a number of you have done check him out sports and more with the madman it's up to you how's business doing it's doing well I'm enjoying it I you know regardless of regardless of the revenue coming in which is average you know it's okay we started off strong which I expected now the grind starts you know successful businesses are built on return customers I'm hoping that the customers that do come through the store for the first time do enjoy their products I firmly believe that anyone who does come through the store buys something for the first time is gonna realize that for the price you know the quality is pretty damn good and so I'm hoping that the power of word of mouth as well as obviously the the Instagram page which I'm working on all the time trying to network trying to bring in you know eyes to the brand and to the business it's only gonna get better from here so how's business doing it's doing really well I'm enjoying it where's that TJ what reaction oh I'm still here yes you are man you're fucking still here TJ what did he lead the league in sacks he I think he was like top three or something look mate TJ what he's coming TJ what will definitely be on the top 100 players of 2019 so I'd say that's when you're gonna see him have you ever smoked well smoked what I've smoked marijuana I've smoked cigarettes but the last cigarette I had was at age 12 believe it or not so yes yes I have smoked cigarettes but not since the age of 12 when I thought it was cool what are some of your favorite music bands we actually answered that in the last video so I won't I won't go through that but I will tell you my my go-to answer that I tell everyone all sorts what made you want to react to NFL videos well I have always loved rugby I've always loved sport and I've always loved athleticism strength power and speed and I can see it in a player in a particular sport so football was always gonna be a sport that I did get into eventually the only thing is that this time for whatever reason I decided to turn the camera on turn on the screen recorder and and do it on camera for the first time ever because I knew that whatever I saw I was most likely gonna enjoy and have an opinion on and I thought you know what fuck it I'm gonna give this opinion to my YouTube audience and that's what happened man it was just one just a random day and I wanted to see some steps I wanted to see the best jokes which I didn't even know they were called at the time the best steps best side steps that the NFL had to offer in comparison to what I've seen in rugby and I enjoyed myself and you did too so here we are that's how it happened man it was all about side steps which NFL player would you choose to be the human ambassador at Alien Contact geez that's a hard one isn't it it's gonna be mental as well as physical I would say you know what I'm gonna go I'm gonna go far left field here I'm gonna go Bernie Kosa what a fucking legend if you could commit to any school only to decommit last second and go to their rival well if I had to say someone I'd say Michigan what's the biggest challenge you face so far in starting your own brand I would say doing everything myself you know not having help not not not teaming up with anyone I guess just literally having the whole entire thing the whole process on my back and then having to negotiate my way through negative comments on YouTube and through that still being able to keep my motivation at a high you know through the trials and tribulations of starting a brand you know all the hurdles and you know all the tasks and hurdles that come along with it keeping that motivation high throughout you know keeping that belief in your product throughout and you know thank God I put in the work at the start to make sure that I had a decent product because right now if I knew deep down that my product wasn't top quality then I'd be worried but I'm not because I'm I'm sure that anyone who does purchase anyone who comes through supports the the products gets products in their hands and and uses them and wears them it's gonna be pleasantly surprised with the quality so you know what nothing good comes easy it's early days talk to me in a couple of years and we'll see what happens what is the one thing you would like to accomplish before the age of 30 geez that's a good question as of this moment I have just over a year and a half until that point and you know what I'm gonna I'm gonna put something out there right now some of you may support me in this some of you may think I'm crazy but before the age of 30 I'm determined to become a professional athlete and I'll leave it there have you watched Peyton detail my brother what have you watched Peyton detail my brother your guess is as good as mine will mkp expand its colors or add patterns absolutely yes when the time is right the next product that will be coming out is the crewneck jumpers they are coming out in just in time for the Australian winter in May which is next month from there we've got hoodies and then as far as expanding I need to take a trip to China to my second manufacturers offices and work through these samples that I've actually had made back in December of last year so I've got 12 garments ready to go once I have the finances to do it and that's all I can really say on that why does Kiwi kicker have a better channel than you this was Kiwi kicker who actually asked this Kiwi kicker Kiwi kicker good old Sam you know it's a hard one because you're my friend but you've also definitely taken food off of my table you know what I mean you know what I mean but you know what from the start I thought it was crack up that you that you did you know choose to use my video model you could say it was a it was you know the highest form of flattery and we have become mates so you know what I'm not gonna agree with you I think my channel is better than yours and I'll always think that but by all means man let's put it to a poll okay favorite NFL highlight of all-time single-play it's got to be March on Lynch's earthquake it has to be that run was ridiculous so sick I actually missed one okay favorite position you wouldn't or couldn't play quarterback it's got to be quarterback man who doesn't want to earn 20 or 30 million dollars a year I mean come on what's the biggest challenge your face so sorry that was last one what do we got here are you ever coming to the States if so come to a Buffalo Bills game Bills mafia will accept you thank you my friend thank you I know they will in fact I'll bring all my bills get but at this moment I canceled my first trip to the US which was meant to be in January and my plans at this stage are to get over there before the end of the year how do you feel about basketball I feel good about basketball I love it it's a great sport I love all sports as you guys know you want to come out to Colorado sometime absolutely let's train in some altitude will you ever react to NFL players highlights when they were in college in brackets do Sonny Mitchell Sonny McCall Sonny McCall running back for who's he running back for I think he's for the the Patriots actually Sonny McCall will you ever react to NFL play lights will you ever react to NFL players highlights from the oncology well of course of course so well it's just you know I've been I have been pressed for time lately as you guys know but once I do have a handle on things then I'll certainly be getting back into the reactions now there was one question back here that I didn't actually answer and that was about smoking smoking weed are you smoking weed again I think that was the question and look guys you know I have a tendency to be over critical of myself I have a tendency to think overthink things and beat myself up for things that I really shouldn't be and you know what in reply to that question as I sit up here on this epic mountain top answering questions for you guys thinking about the future being excited about it you know this just is the cherry on the cake so I'm going to spark this up enjoy it probably meditate for a good 10 minutes up here and then slowly slowly head back down and so the answer to your question is yes yes I am smoking again and all I've got to say is you know what you know what life is too short it's too fucking short guys time is our biggest asset and it's running out life is too short so make the most of it peace out everybody


Should we be blaming the Korean media partially for the passing of Lee Sun-kyun? The internet debate rages on. R.I.P., we're talking about the death, the tragedy of Lee Sun-kyun, more known in America from parasite, but my mister Dr. Brain, other movies, TV shows, endorsements as well. And yeah, the internet is really talking about this because there have been several for many, many years, high profile cases of South Korean celebrities committing suicide, but there's a lot of blame to go around from a lot of corners of the internet. So make sure you like, subscribe, turn on your notifications. Andrew, I guess this is a tragedy, but a lot of people are blaming the Korean media right now, politicians, the police. I don't know if I've ever seen a situation where it wasn't the netizens being blamed. Yeah, because I think in previous situations, like a lot of the K-pop music stars that have passed away, part of it has been, you know, I mean, I think I guess that that happened, I guess in a way more often than actors. So I think that's why this one, especially involving the police investigation, it does raise some eyebrows because it kind of talks about this media storm that was surrounding him leading up to when he allegedly committed suicide. You know, so obviously a lot of people are like, Oh, the media and the police could have laid back and wasn't that serious instead of then him feeling like basically his life was over. Right. I heard that there was politicians involved, too. And it's almost crazy. It is. And I'm not saying this at all to be like facetious at all. RIP to Lee Sung-kyun. Almost like a movie because there's so many layers. Andrew, I saw a conspiracy theory connecting this. And this is from the Korean Internet all the way to the president. Wow. But potentially diverting media attention. Yeah.  It's like a lot of the time you'll be like, OK, it's like depression or what what builds up to depression. And I think from the outside, you might think like, oh, man, it was just like he was just on for marijuana and ketamine charges, bro. Marijuana and ketamine, that's like a weekend in America. You know what I mean? Like those drugs are taken very seriously in South Korea. We understand that's like a different situation. But I feel like from the outside looking in, you're like, oh, that's not that bad. Why did you do that to yourself? You could have like made made it through it, you know, Lee. But then I guess on the inside, we don't know all the details about feeling blackmail, feeling backstabbed, embarrassed, embarrassing your whole family. He was he was pulled from his projects. Yeah. Yeah. Being pulled from his projects, his career going down, knowing that he'll never work in Korea again, as far as in the media, knowing that he could never live a regular life again, feeling like he was interrogated for like 20 hours straight. You know what I mean? So I guess like, we just don't know. I think we're all looking from the outside in. Right. Right. I'm not the most educated on this matter. I'm just doing the internet research like everybody else. Of course, there's people that are there's probably a hundred rings closer to the core of this than we could be, but I will say this. A lot of actors and creatives, but honestly, a lot of politicians and businessmen, they do the same things right in around the world. But it is true that I guess I feel like actors are in a different position in South Korea because they're viewed a little bit and this isn't a lot of Asian cultures, but particularly in South Korea, a little bit like diplomats or ambassadors. Like they have a it's not they're not just entertainers. Right. They're entertainers, but they're also under the scrutiny of like being exalted even beyond that. There's a lot of pressure and pride with being a outward facing entertainer in South Korea. Right. Right. He was part of Parasite, which won an Oscar. Right. Right. Right. So I don't know. I don't know.  But I think on the flip side, Andrew, I will say this. He was going through a lot. Yeah. Like a lot like they were launching. You know, I saw this internet comment that was saying basically they were going against him like he was El Chapo. Like, you know what I mean? Like almost like something on that tier. Yeah. It probably, you know, I don't know all the details because I wasn't following it. I only hear about it now, but like it's based on what I read. It seemed like the whole police and the media were making this a way bigger deal. Like he was almost like the kingpin. You know what I mean? But he wasn't the kingpin. He was not like selling it or whatever. You know, like he was just like a user and got caught up in some things. So I don't know conspiracies. Yeah. I'm not trying to get into it because I don't know. Yeah. Anyway, somebody said, uh, hey guys, uh, of course, like you said Western people were very confused because they said whether he took it or he didn't or he thought it was sleeping pills or was the actual thing. Or he was, he got set up from the top down or whatever. They were just like, I can't understand it because they have very different moral codes in Korea. And somebody said, by the way, guys, do not assume that drug misuse in Korea has treated the same level as it is in the West or especially the US. And somebody said, yeah, I mean, it is true that over there, cannabis is a really big deal to the point where I view it as a comical reaction. Whereas here right now in 2023 in Kensington, Philadelphia, people are shooting up dope on the street and police are right there and nobody even blinks an eye. Um, it is very different, right? Oh yeah. So different, you know, um, somebody said, listen, guys, the media has a way of pushing a decent man over the edge. And I think this is where a lot of the internet comments are right now. Right. Whether it's a combination of the police, the media, the politicians, the netizens, people feel like a good man who he may have indulged in whatever some, some behaviors, but he got pushed over the edge. Yeah. And it seems like it. Yeah. And I mean, being interrogated for 19 hours straight sounds like torture. Yeah. This comment said, listen, um, the, the path forward where there's no redemption. It does create a lot of great products, but the Achilles heel is once you fall off that path, there is no redemption and it is a product of the go hard or go, go home culture that also creates the great products that we love. Yeah. I think there's, I mean, there's definitely some correlation. It's definitely connected. I always say this and I'm not saying that it fully applies to this situation, but there could be some parallels. Andrew, a rocket ship, it either goes to the moon, but Andrew, there is also a very high likelihood that rocket ships explode. Right. Or they have like, you know what I mean? You can explode on launch. You can explode halfway there or you could explode back into this atmosphere. Once the rocket runs out of jet fuel, I don't know what it does for sure. For sure. Somebody said that cancel culture and bullying in South Korea is no joke. Basically saying that the internet, uh, bullying culture, because basically there was a lot of people coming out with the internet thing, uh, comments saying, you know, you get put on a pedestal, but the second you mess up, people can't wait to rip you from that pedestal. Yeah. I mean, um, like we said, there was other, um, opinions and this, this is from the South Korean internet as well, but translated into English. Somebody was saying it was orchestrated by the very top the South Korean president in the first lady because she's under criminal investigation. So they needed a big story to take everybody's attention away. So this is a, it's called what? A dog whistle. This is pretty big. Um, you hear this in America as well, right? Like sometimes they need to release this type of bad news or this type of, uh, this type of person got off. So they release this other piece of news. Right. So that's why it was feeling like a bigger deal than it really was. Yeah. I don't know guys. Let me know in the comment section below. Like I said, I'm not that close to this case at all. I'm just looking on the internet. I see this. I see that. There's so many videos, so many comments coming out of here and there. Somebody said Japan was very successful in reducing their suicide rates recently. People might want to look into their policies and methodologies. Um, yeah, I believe that South Korea is one of the highest suicide rates in the developed world. If not number one in terms of first world countries. Um, I guess somebody said so many talented people in Korea. But why do other Koreans treat them so harshly? And what do you think it is? Because, uh, obviously in Asia, in general people are, but, but I think it varies Asian country to Asian country, but like Confucian countries, they kind of treat superstardom like being the top student. You know how like the other top students are like, man, this guy got all A's, but the second this guy starts messing up, they also want to point out that that guy got caught in a cheating scandal to get those grades or he's not doing it so good in school anymore. Yeah. I just think a lot of things amounted, you know, I don't know what his mental fortitude was, you know, but it's did sound like a lot based off the details. You know, he was confused. He probably felt like he failed his family. He felt betrayed by someone he probably was, uh, in a relationship with he, uh, and then everything can crash now. I mean, listen, there's people who in the stock market crashes. They jump out of a window. All right. You're talking about also I've a lot of Ivy League kids every year. There's freshmen who stopped performing at the same level they're accustomed to in high school and they actually commit suicide. This is pretty common at Cornell in a way and it's not all just Asians. It's a lot of Asians do have a high rate of like being, you know, ashamed and stuff, which leads to, uh, suicide, but actually a lot of everybody like commit suicide. A lot of men actually commit suicide, uh, statistically speaking. So, man, it just feels like, you know, everything he built was coming to a halt and that it was never going to, he was never going to live this down, you know, whether or not he was innocent or not, because in a, in a way, cause he did test negative on the drug test, even if he was innocent, just how it felt was probably just that his life was over. Right, right, right. And he was like deep, like, you know how like a lot of things in life, they kind of like you get through this ditch and then sometimes it's so hard to push out of the other end. But sometimes that ditch feels like it's just like just keep going to drop and drop and drop at the bottom of the ditch. Um, somebody just ended it this way. Somebody said, my mister is my favorite drama. This is a quote from my mister life in a way is a struggle between internal and external forces too. No matter what happens, you will be able to withstand if anything, if you have sufficient internal forces. This is my favorite quote from the drama. Sorry. The external force at this time was too much for you. Rest in peace. Lee Sun-kyun, thank you for your work. Uh, that's a hell of a quote. Honestly, to quote my mister too. Um, ultimately, you know, there's so many takeaways. So many people have so many hot takes. Some people were saying, we need to question the drug laws. We need to question police releasing sensitive information that should stay private. We need to question. This that thing, the internet bullying needs to have more restrictions. There were so many commentaries, obviously to be fair to enter. Some people blamed Lee Sun-kyun himself for his decisions, right? Right, right. I mean, you know, he did make certain decisions that led him into this situation where things could go terribly wrong. Right. Um, and I guess that that's what has everybody so wrapped up in this, right? Yeah. I think ultimately this is my takeaway. RIP, uh, he's leaves behind two children, a wife. Um, I think that the one hope that I have is that they change the laws to make sure that these investigations aren't as public because here's the thing, Andrew, politicians and I'm not saying the craziest conspiracy theories are true or not. Politicians will use celebrity news. If everybody knows they follow that celebrity to divert from their situations. Yeah. And they don't, they are not like they say and the politicians, they oftentimes control have a potentially, um, control like the legal system a lot more than an actor does. Oh, yeah. Like an actor has the attention of the world or the global market, but they don't control the infrastructure mechanisms. Yeah.  I think it's the actor. I think the politician wins because the politician is more entrenched. They're on the inside. Yeah. So, um, but I will say this. I'm not going to tell Asia how to treat drug laws either. You know what I mean? I think over there, Andrew, in the West, we are experiencing probably drug problems. Oh, yeah. So, so I'm not going to be like, we'll just loosen them. Let everybody let Asia turn into. I don't know. That's not a good idea either. I don't think that's the solution. I do think how the media handles things and things being public and the investigation probably was too harsh. I don't know how many did someone get killed or something like this sounds crazy. Like the amount of attention on these charges from what I read sounds uncalled for. I'm not saying he shouldn't lose even his job over these allegations because people lose jobs over all types of allegations, you know, and it's fair because you work a corporate job. You can lose your jobs are very serious over there. So I'm saying that. But like to get all this, I don't know. It sounds it sounds what do you think? Last point about Asia's culture of shame because a lot of people, like I said, you know, a lot of I've said this before Andrew, like, you know, like when you come from an academic Asian family, it is true. Bees are really frowned upon because if you get bees, you can't go to the hyper elite institutions or get scholarships and go to the league.  Like, so I guess that same pressure, it does produce diamonds, but sometimes the end of the pieces of coal that if they're pressurized turning the diamond, sometimes those pieces of coal just disintegrate to. Yeah. So I just don't know. I mean, I wish that they could play with the sliders. I don't know if they need a fundamental shift of how they do it. There's a lot of pros and a lot of cons to every methodology of how every system culture runs their algorithm. But you know, I think cases like this, RIP, Lee Sun, they cause a time to step back and reexamine. But how much will really realistically change? I'm not sure. Let us know what you think in the comment section below. We encourage the debate until next time. We're going to hop out boys. We out. Peace.


Hi, welcome to another music theory lesson. Today's lesson is for the vertical theory students and this is vertical theory number eight and this is a lesson on cadences in music. Now a cadence in music is very much like punctuation. Cadences can fall into a lot of categories just like punctuation does. They can serve the role of a period or they can serve the role of a comma and we're going to try to define these various cadences as they work in major and minor keys and it's a it's a good little lesson here and we'll hopefully get you really really seeing cadence as well as we get into the next couple of lessons. There are two different kinds of cadences that we're going to deal with today and these are sort of the big descriptions. There are final cadences and there are progressive cadences. All right, and we're going to deal with each of them. When we're in a key, a final cadence is a cadence that serves the role of a period in pros. So final cadences can be two things. In a key, they can be a 5-1 progression or in a minor key, they end up being a 5-1 progression. Okay, that would be one type of final cadence and the other kind that we see of final cadences would be a 4-1 progression or in a minor key, it ends up being a minor 4 to a minor 1 and you should know how those relate to each other based on some of our previous lessons. So those are our final cadences. We're going to name those in a minute. Our progressive cadences are really fit into two categories as well. Our progressive cadences could be a 1-5 or a 4-5 in major or minor and the other type is a 5-6 cadence or a 5-6 in minor. Okay, so we're going to dive into each of those just a little bit more in a little bit more detail. Okay, so let's start with our final cadences and we're going to show you how these look and how they work. Our first final cadence I mentioned was the 5-1 progression. We call this a final authentic cadence. These are probably the most common and strongest cadence that we have in Western music. You're going to see them all through the music that you're learning. So we're going to see them all the time. Let's give you an example of a 5-1 cadence. If we have a key signature maybe of one sharp F-sharp, then our one chord would be a GbD, a G major chord. That's our one chord. So the five chord would be D F-sharp and A five. So when we're analyzing the music, if we see something that looks like this, that really is very strongly a 5-1 or an authentic cadence bringing us to some place of rest on the one chord. These happen at the end of phrases. They happen at the end of verses and they happen at the end of songs. 5-1 cadence doesn't matter if it's major or minor. If it happened to be a G minor, we'd have a Bb there. But that's our 5-1 cadence, a final authentic cadence. The other kind of cadence and the other vocabulary turn that we have here is the 4-1 cadence and we call that a final plagal, P-L-A-G-A-L. So let's get into a key. Let's put a B flat there. So we're in the key of F. So our one chord in F would be an F, A, and a C. Boom. Put our ending there. And the four chord would be a C major chord in the key of F, which gives us a 4-1 progression to some place where we're stopping. We'll put even a fermata there. That's the end of the song. And that is a 4-1 plagal cadence, final plagal cadence. You'll see that all over the place. Now, you also might see it in some inversion. So it wouldn't be odd at all. Let's see if I can take that note out. Maybe you would see the final plagal looking something like that, which would be an inversion. So really, what we've done is made a 4-6 going to a 1 and that would be very common. Wouldn't be something that would be a problem at all. Okay? Same with those five chords and the final authentic cadences. Okay, so that's what you're looking for for the final plagal. Let's move now to our progressive cadences. We've got two different kinds. Our first kind of progressive cadence is the progressive half, progressive half cadence, which is a 1 to a 5 or a 4 to a 5 at some place of rest. So let's assume we're in the key of D. Okay? Our one chord would be a D major chord, so something like this. And then it would go to a 5 chord, which is an A major chord, something like this. And I'll bet you there might be a fermata here or maybe a comma there or the end of a phrase, something that tells us that that one five progression is somehow acting almost like a comma before we go on to the next thing. A place of rest, a half cadence, is a 1 to 5. And it might be very similar if we had a 4 to 5, progressive half. And then finally, our last type of progressive cadence is when we have something like a 5 to a 6 or a 5 to a major 6, if it happens to be in a minor key, we're going to stay in the major keys for now. But a 5, 6 cadence would look something like, let's just pick another key. We'll go with two flats, B flat and E flat. So we're in the key of B flat major. So a 5 chord and B flat major would be an F chord. So F, A, C would be our 5 chord. And it's progressing then to a minor 6 chord, which would be G, B flat, D. So maybe something like this, this, and maybe even an inversion where we have something like a 5 to a 6. And that would be the 6, 4 inversion. And there we would have a progressive, it's called progressive deceptive. So we here have a progressive deceptive cadence. All right, so at this point, you know that you've got four options, you've got final authentic, you've got final plagal, you've got progressive half, and you've got progressive deceptive. These are your four options of cadences. So let's just give you an example of what you're going to see in your assignment. You're going to see a series of chords. And what I want you to do is analyze them within the key that you're working. So here you're going to go, okay, there's no sharps, no flats, I'm sintering around C, let's say that we're in C major. And you'll go, okay, I've got a 1 here, I've got a 1 here, I've got a 5, I've got a 1, and I've got a 6. Okay. And from there you'd go, okay, a 1 to 1, okay, that's none of the cadences. A 1 to a 5 is a progressive half. So that's that one. A 5 to a 1 is a final authentic. And a 1 to a 6 is a progressive deceptive. And here you will have done exactly what I want you to do to complete the assignment. After that, then you have some situations where you can write your own chords in. Those chords can all be written in root position. They don't have to be in inversions. And you'll be good to go. So we're really just getting used to cadences at this point. Good luck. I hope this explains it well for you. And go to work and try to get this thing finished up.


Hello and welcome to the session. In this session we discussed the following question which says a number of two digits has two for its units digit and the sum of the digits is 1 upon 4 of the number itself. What is the number? Before we move on to the solution, let's see one fact which says that a two digit number a b in which b is the units digit, a is the tenth digit is written in the general form as 10 into a plus b. This is the key idea for this question. Now let's move on to the solution. In the question we are given that the units digit is given as 2 where 0 let the tenth digit be equal to x. So now we have got the tenth digit also that is x and the units digit that is 2. So the two digit number is given by 10 into the tenth digit that is x plus the units digit that is 2 this is equal to 10x plus 2. So this is the number formed when we have the units digit as 2 and the tenth digit as x. Now the sum of the digits that is sum of the units digit and the tenth digit is given as 2 plus x. Now according to the question we have that the sum of the digits is one fourth of the number itself. So this means we have 2 plus x is equal to 1 upon 4 of the two digit number formed that is 10x plus 2. So this further gives us 4 into 2 plus x is equal to 10x plus 2 that is 8 plus 4x is equal to 10x plus 2. This gives us 10x is equal to 8 minus 2 which is further equal to 6x is equal to 6. So on dividing both sides by 6 we get x is equal to 1. Now we have assumed the tenth digit to be x. So we get the tenth digit is equal to 1 and we have already given the units digit as 2. The required number is equal to 10 into the tenth digit that is 1 plus the units digit that is 2. This is equal to 10 plus 2 equal to 12. The answer is 12 is the required number. So this completes the session. Hope you understood the solution for this question.