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This is absolutely informative and explanation was done in lucid and clear way. I would recommend this to other engineers as well. Thank you for making us aware these theories.
Better explanation sir.. But one point is not coveted that VC is constant value and RC is variable... Best explanation for VC.. really comprehensive...
May be not always but usually. Think as per assembly. Shaft or any part is big in size will cause problem. Will have less chance to be with available space. MMC is that case. While same with hole small hole or slot will cause problem in assembly, i.e. Again its MMC. In very few cases LMC causes worst case. For that you can check last video in gd&t series.
Hello, I have a confusion with bonus tolerance. If the shaft is at LMC means 9mm but modifier is .1mm then it can total increase upto 11.1mm, means bonus tolerance is 2mm + gtol .1mm = 2.1 total tolerance. But why shall it be minus from LMC as you mentioned in RC of shaft = LMC- GTOL-BONUS, it should go 9-.1-2 = 6.9mm, I think while getting bonus in shaft everything should be on plus (shaft can be curved that the allowance). How can the shaft dia be less than 8.9mm? Let me know if I am wrong.
Bonus is for form or location not for size. Suppose a shaft of 10+-2 and gtol.1 at mmc. It means when shat at mmc 11 it there wll be.1 location tolerance on it. But suppose shaft is at 9 so it can have more allowance to move as it is small that will be 2.1.. So bonus is always amount of departure of shaft from mmc. If manufactured dimension is 9.5, we get bonus of 1.5 only. Plz watch gd&t lectures those clarifies more. Let me know if you need further explanation. Thanks
It is important to point out that in the case of Screws and Washers Virtual Conditions are not considered .. Only when you have studs or pin on a plate are positional / virtual tolerances considered .. Likewise with the washer .. In a plate with many holes then the virtual conditions are assumed to be required ..
As you have mentioned, In case of R C for Bonus tolerance if shaft is manufactured at its LMC , RC will be = LMC - 0.1 (G Tol) - 2 (Bonus Tol.),= 7.. In this case we are reducing Shaft Dia much.. I am not able to understand significance of Bonus Tol. And where it shall eb used. Could you please guide in detail..
We are not reducing the size, these are virtual things. If shaft get manufactured at LMC that is it has allowances of location of. 1 and as it is smallest size, further location allowance is 2 that is bonus. Size of cross-section can not be less then stated size and size tolerance. Plz let me jnow if this clarifies.
This is a very very misleading methodology .. The explanation is good but the driving methodology is very bad .. It is always assumed that the Shaft always drives the Hole Tolerances .. It should be explained this way .. I know that ASME Y14.5 doesn't do a very good job at driving this home either .. When you are a design engineer you are looking for the shaft to drive the hole .. This is true for one shaft mating with one hole .. This is not true with multiple shafts mating with multiple hole as in an assembly .. It is important to discuss the machines which produce shafts and holes and discuss their limitations so we can understand where these tolerances come from .. It is the machines limitation which drives the tolerance of components .. Knowing this allow us to "Design for Manufacturing" .. This concept is every bit as important because knowing how tolerances are driven is key to the manufacturing process .. Second is DFA "Design for Assembly" Design for assembly now moves us to multiple stacked tolerances and multiple machines .. The idea is not to design to the machines limits .. The Idea is to drive design to repeatably which everyone calls 6 Sigma .. This takes experience with vendors and their machinery .. It is important to know your factories Q.A. schedule for their machines .. You have to ask these questions to get a good feel for what tolerances you can expect .. So I recommend that you start over and talk about how the shaft tolerance will drive the hole and its tolerance .. We can all move the tolerance boundaries in one direction or another just by changing the diameter and the tolerance .. The trick is not to have to do this .. It is important to keep the tolerance simple because GD&T can create confusion with machine programmers .. I come at this from a manufacturing process control & top down design methodology point of view .. I believe it is more important to know your vendors and their capabilities and in this way you can expect a certain level of quality 100% of the time .. GD&T doesn't guarantee 6 Sigma if you vendors can't understand what they need to accomplish .. It is important to note that I can purchase components from a manufacture for 60% less money if I use standard tolerances rather than GD&T notation .. If you are very demanding and require extreme tolerances then you are going to have to find very specialized vendors .. GD&T may help when we are talking about very tight tolerances .. GD&T doesn't make it easy for them .. They have to hire a person who understands GD&T and he must know the machine that he is programming to achieve the tolerances he or she is programming the machine for .. Disclaimer: These are my opinions from 27 years of mechanical design experience .. I am sure others will disagree with part or all of what I have written but, again it depends upon their experiences .. My background has always been to drive costs out of assemblies this is known as DFC "Design for Cost" .. So this is where I am more value conscious and I place a high value on value engineering ..
after Bonus RC = LMC-G TOL-BOUNUS it means LMC OF SHAFT is 9mm and G tol is 0.1 and bonus = 2 So RC= 9-0.1-2 == 6.9 mm dia also acceptable in production?
Nice explanation for a person having basic GD&T knowledge, which is must for stackup analysis. But you need to provide diameter symbol before Gtol. Becoz tol zone is cylindrical and can't be one directional.
Two plane rotated around a axis makes required envelope. It good to put symbol but it doesnot makes onedirectional. And tolerance always circular not rectangular.
When you are not putting dia symbol it represents a rectangular tol zone. You might be aware. Technically not putting the symbol is not a mistake, but it's less accurate. I didn't understand what you meant by there is no rectangular tol. Profile, form has gdnt callouts which are non circular also. It depends on specifying the diameter symbol.
@@nayan2596 yes I know what u are saying it should be mentioned. I specifically told regarding positional tolerance. Otherwise for flatness it will be two parallel plane only. Tolerance zone is always depends on type of gtol and even how we are presenting it. But It can not be one direction that is what I said as even primary datum locks 3degree of freedom. And if it is axis it locks 4degs that is what i meant.
Thank you for the informative video. I have one query. As per ASME definition RC is worst case scenario, but you are telling its best case scenario. Could you please explain the difference between virtual and resultant condition in Layman terms for better understanding and to avoid confusion between VC and RC.
lok chand santosh kumar , yes correct. At time of explanation I was thinking for shaft that's why I explained this way. Next lecture includes this. Let me know if other improvement points as well.
What is total allowable tolerance of shaft become LMC Size? Shaft size- 20+/- 0.1, GTOL frame is perpendicularity dia. 0.1 m Modifier is there. Please answer as per your convenience. Thanks
Hi Amit, sorry for this late response. on shaft being LMC i.e. 19.9 it will have bonus of .2 as M modifier is there. so total allowable tolerance will be .2+.1 = .3, let me know if this clarifies your question. thanks
I think the modifier is wrong, it says the true position will only be activated at M which is Maximum Material condition. But you activated it for LMC should have been L for the condition you described. Or Logically It will be activated at M and then RC= MMC+GTOL+Bonus. Which means when the shaft is biggest it should be centred as it will be hard to insert.
@@TheEssenceofknowledge For the shaft you have to look at the worst possible condition. That would be shaft at its biggest, when mating with the hole it will have issues as a small shaft will fit ... a big shaft won't fit. Which means Worst case scenario = MMC of Shaft + True center of the shaft is displaced. If the true center is displaced, that will result in an effective diameter of 0.1+0.1 when the shaft is moving (you can look at it from a Gaussian curve or from 2 point method... ) So True center will only be activated when M (M here stands for MMC according to the notations) is met .. which is the maximum material condition of the shaft. So now the worst case for a moving shaft in a hole is : Worst case scenario = MMC of Shaft + True Center offset (0.1)+ Bonus when moving ( 0.1)
@@Darthvader81498 yes correct worst case is VC. That do not carries bonus. Bonus is the case when MMC modifier is in Gtol frame. So virtual condition is VC=MMC +Gtol for shaft. VC= MMC-gtol for hole. No bonus is in VC. RC is best case. Bonus we get when manufactured dimension departs from MMC towards LMC. And bonus is equal to amount of departure. RC is best case when shaft or hole is at LMC. RC= LMC-GTOL-BONUS FOR SHAFT. =LMC+GTOL+BONUS FOR HOLE. This is as per ASME 2009 Y14.5. let me know if this clarifies you.. thanks
@@TheEssenceofknowledge best case scenario kind of defeats the purpose of stackup analysis. Also when the GD&T box has M it is only applicable during MMC. M modifier means MMC
@@Darthvader81498 not only applicable to MMC, it is thru out. That gives Bonus. It means, if shaft manufactured at MMC we get only Gtol mentioned. But if manufactured dim departs from MMC we get bonus of amount of departure as a form or position error that is allowable. at LMC we get max bonus. Now if someone uses LMC modifier L in frame concept reverses and we get bonus when dim departs LMC. The formula and the concept is from ADME2009 Y14.5.
Thank you! A quick question from 12:42 to 12:50. Shouldn't the re4sultant condition be MMC-GTOL-BT instead of LMC-GTOL-BT. In tha case your shaft becomes 9-0.1-2 = 6.9mm. Shouldn't it be MMC-GTOL-BT which would be 11-0.1-2 = 8.9mm?
If mmc modifier is in gtol frame, RC is always based on LMC. MMC will be in calculating VC. RC for a shaft is at smallest sizen of shaft and considering hole where it is assembled is at true position and at biggest size. This LMC - gtol - BT does not imposed on size tolerance zone. Do not confuse that shaft can be manufactured at RC, in manufactured dimension limits of size always respected. Let me know if this answers your question
Bonus is actually variable should be referenced to manufactured dimension. Bonus is MMC-manufactured dia. In case it manufactured at LMC.. we get 11-9 that is 2 mm. Let me know if this clarifies.
Bonus is like additional tol for positional error we get. If part is manufactured at MMC we get the Gtol mentioned as positional error. But when it departs towards LMC we get bonus of amount of departure. When it is manufactured at LMC we get max departure that is MMC-LMC. So that is best case bonus. Let me know if this clarifies your query.
Hi, yes correct. I think this thing we discussed before 2 month as well. Next lecture includes that. And while explaining I was thinking of shaft so gone this way.
Transition fit toleraces are generally too precise. Here tolerance zone is. 5. Study bearing for transition tolerances. Skf provides good detail. Like 10 mm, keeping 10 as base bore tolerance should be - 8 micron to 0 micron. Shaft can be h6, h8, j5 or j6 depending on condition and requirements. Let me know if this helps and your further queries
Thank you sir..... What are you teach I understand.... But my doubt...I will make one shaft(DIA 5) with assembly, shaft will come MMC=6 , and also hole will come MMC=4, How to assemble that part.
if you make shaft of 5±1 its VC = MMC = 6. Always hole vc should be equal or greater than shaft vc i.e. hole VC = 6 = mmc of hole. Now we know hole MMC = 6, Hole LMC = MMC + tolerance, suppose tolerance is 1 so lmc hole = 6+1 =7 so hole dimension must be 6±.5. this is how it goes. let me know for further clarification. Thanks.
@@narenmids sorry for late reply. I have said hole MMC 6. So it cant be 5.5 it will be more then 6 always. Let me know if I am not getting you correctly. Thanks
Modifier m means that the MMC is important and gtol is applicable if part manufactured at MMC. If manufactured size departs from MMC we get bonus of amount of departure and Max bonus is available if component manufactured at LMC. Modifier M is for MMC showing it is important. Modifier L shows LMC is important and we get bonus when size departs to MMC from LMC. Let me know if this clarifies. Thank you!!
for calculations yes. Actually the Bonus is amount of departure. Suppose Shaft manufactured at MMC will get 0 bonus, If shaft shaft manufactured departs from MMC towards LMC, we get actual bonus as amount of departure. Let em know if this clear.
sorry for late reply, I was travelling. by calculating VC and RC we get a single size and tolerance replacing size its tolerance and GTOL. that we can use in stack-up. please let me know if this clarifies.
For RC condition of shaft , Why do you need to add bonus tol... logically if you consider virtual condition at LMC(THAT IS LMC+GTOL) for resultant condition,Then it's very much looks logical and acceptable right..... I know it's written in book.but by which logic we are adding bonus to it....I want to say you add LMC & GTOL ,I am ok with that but why adding BONUS TOL alag se....please explain the logic behind it but please don't quote lines from book..
Hi Saurabh, I never used a book. The things I have explained in here are always from my 11 years of experience and ASME Do you understand what Bonus is? Suppose as a designer for a shaft MMC is critical to me as per assembly so I have given MMC modifier in gtol frame. That allows a manufacturer to have a form error of gtol + the amount of departure from MMC and eases manufacturing processes. That is why we add bonus. Please watch couple of lecture from my GD&T sessions it will clarify more. Let me know if this helps.
Bonus tolerance is the amount of departure from MMC. Suppose a shaft 10 +-1. And gtol of.1 and modifier is mmc given in frame. If shaft at its MMC that is 11 we will get no bonus. Now suppose shaft manufactured at 10, amount of departure is 1 so bonus will be 1.0 and gtol is..1 so total tolerance 1.1 now suppose it is at 9 i. E. Its LMC for resultant condition we get max bonus of 2, this is amount of departure and gtol is. 1 so total tolerance wll be 2.1 at resultant condition. Let me know further query. Thanks
Hiii sir,I saw ur lacture vedio it is very helpfull for me,so thanks for u, I want to know about how to relate flat tolerances to the position tolerances on same face.
Karan, not sure in which ref you are asking but position will control it location with respect to a datum where as flatness contols form means surface lies between two parallel plane irrespective of any datum. Let me know ur further query. Sorry for late response
Sir even if u consider RC, Should the Gtol be positive? like RC=LMC+Gtol, bocoz u know if whatever way it shifts then that much dia of hole is needed to fit right?
For a hole if MMC modifier is used, the Resultant condition is when hole is produced at biggest size that is LMC and it is dislocated by Gtol and bonus. It will be LMC + Gtol + Bonus
Position tolerance will usually be symmetrical tolerance but you are explaining it as tolerance applied in single side of the shaft ... Correct me if am wrong
Positional envelope will be a cylindrical one, so it is always symmetrical. But In real case shift is posible one side only at one time. That is why I am explaining so. Formulas are correct, you can see images in video or refer ASME 2009. Let me know if need more details.
Tq sir.. It is wonderful explanation..but, I have a doubt in this lecture that what will happen on both shaft and hole if we given lmc modifier.. Pls kindly explain this doubt sir.. Tq..
With LMC modifier the LMC condition will be important and we get Only mentioned Gtol.. as component departs towards MMC condition we get bonus. I have explained in one of the video. Thank you!
Sir, in this video you were said if Gtol got (M)modifier there the shaft will manufacture smaller.here my question is if Gtol got modifier (L) what will happen. More over here as per the RC formula the shaft dia get 6.8 (LMC-Gtol-bonus.9-0.2-2=6.8). But the shaft LMC is 9. Here the shaft dia-6.8 ( as per the RC formula) this 6.8 dia is so exceed the LMS dia 8.is it possible?
@@vijayg1776 the answer for that is cross sectional size must be with in size tolerance limit. Suppose a shaft 10+-1. All cross ection must be between 11 and 9. But suppose it is distorted all the way in lenght by 1mm it will have envelope of 12. Mini size of hole will be 12 because of form error. VR and RC are virtual effect of form errora. Size tolerance must be respected everywhere.
6.8 is resultant condition boundary not diameter. It like common boundary of shaft manufactured at LMC and displaced by given gtol and bonus in all directions.
Sir, Once we are calculating VC & RC of shaft, how decide the counter matting part hole Nominal dia, hole feature tolerance and position shift.?????. Thanks in advance.
KARTHIK Ramasamy , the virtual condition of shaft should be virtual condition for hole. Once you calculated vc of shaft you will know what minimum hole dia you need. Then depending on fit needed decide dim. Suppose it's a dowel pin hole, you should select transition fit.
I have just started with the whole understanding of this GD&T and thus have a question regarding it. What are the different types of GD&T courses do we need to study in order to study this whole subject? I guess Stack up terminologies are one of them. Can you name the rest? Thanks!
Refer ASME 2009. Y14.5. It shows Dimensioning and geometric tolerances for drawing. Stack-up is study of tolerances. Similar things are like DFMEA, SIX SIGMA etc. This will be enough for defining a geometry on drawing. You can learn CAD, FEA software to enhance further more on design side. Always keep basics of design with these skills. Let me know if more queries. Thank you.
Sir pls clarify my boubt sir, we calculating virtual condition of shaft..reason for..minimum size of hole to accommodate the shaft, it is reason for calculating virtual condition. But resultant condition, we are calculating for shaft ..why are calculating..what are types of reason. Can you please elaborate explain this
Many time loose fit also may result in many issue. So we calculate RC. That is why RC and VC used in tolerance stack up analysis to get max clearance and min clearance or interference. Let me know if this clarifies. Thanks.
@@vijayprakash8666 thanks Vijay. Last 8-9 months never been easy for me. Was dealing with few bad things. Now bad phase over. Planning to new start. Soon will be back. Thanks Vijay.
@@TheEssenceofknowledge .thank you for your reply sir.waiting for u vedio sir.not only me, many people eagerly waiting for u r vedio, pls as soon as possible putting vedio..your explaining spr sir, easy to understand sir.. Sir can you pls share material , my mail id vijayprakash305@gmail.com
I m not sure at which point you aking but RC for hole is lmc + gtol + bonus. And bonus is maximum amount of departure that is LMC of hole - MMC of hole. Please let me know further query
Bonus tolerance is only available during best condition that is at resultant condition when shaft become smaller or hole become bigger. Suppose shaft size 10 +-1 so when it get manufactured at 9, we get bonus of 2 and deducted while calculating resultant condition.
I have not much Idea regarding hinge buttons.. I will check and get back to you. If you have any rough sketch of parts I can guide better. If we are doing stack up for polar dimensions, all dimensions should be in that or we will need to convert them in linear form.
I have this question from my work. A dimension of a part has a position tolerance of 0.35 mm. Inspection report from supplier says 0.470 which was accepted and in comments he said "according to MMC up to 0.555". My question is bonus tolerance is applied only to hole right? or also for position? How can position tolerance be 0.555?
sasi r, actually bonus tolerance applied only when modifier MMC is in gtol frame. Suppose your dimension is 10+-1 and gtol is given of .35 with MMC. It means when dimension manufactured is 11 that is MMC you will get only position tolerance of .35. but now component manufactured at 10 that is departure from MMC is 1 mm, in this case you will get 1.35 mm of position tolerance. And now suppose it get manufactured at 9 that is it's LMC, Its departure from MMC is 2 mm you get position allowance 2.35 mm. This additional we are getting is bonus. I explained you for shaft or block. Same will happen with hole or slot. Bonus is applicable to all dimensions if gtol has modifier. Let me know if you have further questions. Thank you. Watch GD&T session it will get more clear..
Ram Kumar , I will cover details about runout in GD&T lectures, but the value of tolerance is always a functional requirement. Suppose we need a very fine gap, than based on stackup analysis tolerance value will be decided. Let me know if you have any specific case, I can guide you for the values.
Amardipsinh Rahevar , MMC is Maximum material condition, Gtol is geometric tolerance. MMC for shaft or hole is when feature will have maximum material where as virtual condition for a shaft is minimum size of hole required to accommodate it in its worst case. What is worst case for shaft, when it is at MMC+ position or form error of Gtol. Same way for hole virtual condition, max Dia of shaft it can accommodate in its worst case. What is worst case of hole, it is it's MMC - form, position error(Gtol).
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Most difficult things explained in easiest way, best tutorial for stack up in youtube. Highly recommended for mechanical engineers.
Thanks Siddhartha!!
Thank you very much , you have given a great explanation on stack up analysis that is very important for a design engineer!!!
This is absolutely informative and explanation was done in lucid and clear way. I would recommend this to other engineers as well. Thank you for making us aware these theories.
Thank you!!
Better explanation sir..
But one point is not coveted that VC is constant value and RC is variable...
Best explanation for VC.. really comprehensive...
Yes correct RC is variable... I just put the extreme one for worst case tolerance stack up. Thanks.
Explanation was very good i enjoyed your lesson sir now i am very much clear about it thank you sir....
why is worst case of a shaft always mmc ! why not lmc? similarly for hole
May be not always but usually. Think as per assembly. Shaft or any part is big in size will cause problem. Will have less chance to be with available space. MMC is that case. While same with hole small hole or slot will cause problem in assembly, i.e. Again its MMC. In very few cases LMC causes worst case. For that you can check last video in gd&t series.
Hello, I have a confusion with bonus tolerance. If the shaft is at LMC means 9mm but modifier is .1mm then it can total increase upto 11.1mm, means bonus tolerance is 2mm + gtol .1mm = 2.1 total tolerance. But why shall it be minus from LMC as you mentioned in RC of shaft = LMC- GTOL-BONUS, it should go 9-.1-2 = 6.9mm, I think while getting bonus in shaft everything should be on plus (shaft can be curved that the allowance). How can the shaft dia be less than 8.9mm? Let me know if I am wrong.
Bonus is for form or location not for size. Suppose a shaft of 10+-2 and gtol.1 at mmc. It means when shat at mmc 11 it there wll be.1 location tolerance on it. But suppose shaft is at 9 so it can have more allowance to move as it is small that will be 2.1.. So bonus is always amount of departure of shaft from mmc. If manufactured dimension is 9.5, we get bonus of 1.5 only. Plz watch gd&t lectures those clarifies more. Let me know if you need further explanation. Thanks
I have the same question.. please clarify it here. It will be very helpful
Very nice explanation. Thanks for such a simple and complete explanation on this subject. Keep posting.
It is important to point out that in the case of Screws and Washers Virtual Conditions are not considered .. Only when you have studs or pin on a plate are positional / virtual tolerances considered .. Likewise with the washer .. In a plate with many holes then the virtual conditions are assumed to be required ..
Sure Thanks, will try to include your points in coming..
As you have mentioned, In case of R C for Bonus tolerance if shaft is manufactured at its LMC , RC will be = LMC - 0.1 (G Tol) - 2 (Bonus Tol.),= 7.. In this case we are reducing Shaft Dia much.. I am not able to understand significance of Bonus Tol. And where it shall eb used. Could you please guide in detail..
We are not reducing the size, these are virtual things. If shaft get manufactured at LMC that is it has allowances of location of. 1 and as it is smallest size, further location allowance is 2 that is bonus. Size of cross-section can not be less then stated size and size tolerance. Plz let me jnow if this clarifies.
@@TheEssenceofknowledge Thank you got it
@@TheEssenceofknowledge , one more query sir, this do we need to consider Bonus tolerance during Stackup Analysis..
@@abhijeet2816 yes if mmc modifier is given we need to consider, it will help us to give find the max gap.
Very well explained.tq sir for sharing your knowledge.👍
This is a very very misleading methodology .. The explanation is good but the driving methodology is very bad .. It is always assumed that the Shaft always drives the Hole Tolerances .. It should be explained this way .. I know that ASME Y14.5 doesn't do a very good job at driving this home either .. When you are a design engineer you are looking for the shaft to drive the hole .. This is true for one shaft mating with one hole .. This is not true with multiple shafts mating with multiple hole as in an assembly .. It is important to discuss the machines which produce shafts and holes and discuss their limitations so we can understand where these tolerances come from .. It is the machines limitation which drives the tolerance of components .. Knowing this allow us to "Design for Manufacturing" .. This concept is every bit as important because knowing how tolerances are driven is key to the manufacturing process .. Second is DFA "Design for Assembly" Design for assembly now moves us to multiple stacked tolerances and multiple machines .. The idea is not to design to the machines limits .. The Idea is to drive design to repeatably which everyone calls 6 Sigma .. This takes experience with vendors and their machinery .. It is important to know your factories Q.A. schedule for their machines .. You have to ask these questions to get a good feel for what tolerances you can expect .. So I recommend that you start over and talk about how the shaft tolerance will drive the hole and its tolerance .. We can all move the tolerance boundaries in one direction or another just by changing the diameter and the tolerance .. The trick is not to have to do this .. It is important to keep the tolerance simple because GD&T can create confusion with machine programmers .. I come at this from a manufacturing process control & top down design methodology point of view .. I believe it is more important to know your vendors and their capabilities and in this way you can expect a certain level of quality 100% of the time .. GD&T doesn't guarantee 6 Sigma if you vendors can't understand what they need to accomplish .. It is important to note that I can purchase components from a manufacture for 60% less money if I use standard tolerances rather than GD&T notation .. If you are very demanding and require extreme tolerances then you are going to have to find very specialized vendors .. GD&T may help when we are talking about very tight tolerances .. GD&T doesn't make it easy for them .. They have to hire a person who understands GD&T and he must know the machine that he is programming to achieve the tolerances he or she is programming the machine for ..
Disclaimer: These are my opinions from 27 years of mechanical design experience .. I am sure others will disagree with part or all of what I have written but, again it depends upon their experiences .. My background has always been to drive costs out of assemblies this is known as DFC "Design for Cost" .. So this is where I am more value conscious and I place a high value on value engineering ..
I cant say its misleading, I understood your concern. Thanks for detail explanation.
after Bonus RC = LMC-G TOL-BOUNUS it means LMC OF SHAFT is 9mm and G tol is 0.1 and bonus = 2 So RC= 9-0.1-2 == 6.9 mm dia also acceptable in production?
No, cross section must be with in size limit.. these are virtual limits..
Good work bhai!!👍
Thank you!!
Chala bhaga chapparu sir, very good & simply explanation
гарний козак. і сорочка гарна. я йому вірю. !!
Vry nyc..
Explanation is perfect for fresher....!!!
Thank u sir
Nice explanation for a person having basic GD&T knowledge, which is must for stackup analysis. But you need to provide diameter symbol before Gtol. Becoz tol zone is cylindrical and can't be one directional.
Two plane rotated around a axis makes required envelope. It good to put symbol but it doesnot makes onedirectional. And tolerance always circular not rectangular.
When you are not putting dia symbol it represents a rectangular tol zone. You might be aware. Technically not putting the symbol is not a mistake, but it's less accurate.
I didn't understand what you meant by there is no rectangular tol. Profile, form has gdnt callouts which are non circular also. It depends on specifying the diameter symbol.
@@nayan2596 yes I know what u are saying it should be mentioned.
I specifically told regarding positional tolerance. Otherwise for flatness it will be two parallel plane only. Tolerance zone is always depends on type of gtol and even how we are presenting it. But It can not be one direction that is what I said as even primary datum locks 3degree of freedom. And if it is axis it locks 4degs that is what i meant.
Thank you for the informative video. I have one query. As per ASME definition RC is worst case scenario, but you are telling its best case scenario. Could you please explain the difference between virtual and resultant condition in Layman terms for better understanding and to avoid confusion between VC and RC.
you are the awesome explanation is pretty clear. please do share more topics about GD& T and Stack up analysis.
sure, I will do so. Thank you!!
Hi,
While explaining the Vc for shaft,you can tell that minimum dia of hole is req to accommodate the shaft...instead of using maximum dia of hole...
lok chand santosh kumar , yes correct. At time of explanation I was thinking for shaft that's why I explained this way. Next lecture includes this. Let me know if other improvement points as well.
Sure.
thanks for making this tutorial. and it is very helpful for me.
I've been looking for some guidance. Your videos are very helpful. Thank you very much for sharing them.
Thanks Devam, I am happy if that helped.
What is total allowable tolerance of shaft become LMC Size? Shaft size- 20+/- 0.1, GTOL frame is perpendicularity dia. 0.1 m Modifier is there. Please answer as per your convenience. Thanks
Hi Amit, sorry for this late response. on shaft being LMC i.e. 19.9 it will have bonus of .2 as M modifier is there. so total allowable tolerance will be .2+.1 = .3, let me know if this clarifies your question. thanks
@@TheEssenceofknowledge yes thanks
Why we should use MMc and LMC terms in manufacturing drawing,instead of it we can use tolerance itself know.what is the need of it .pls clarify it.
These modifiers in gtol tolerance allows more form or orientation tolerance when size produces is not on critical value.
I think the modifier is wrong, it says the true position will only be activated at M which is Maximum Material condition. But you activated it for LMC should have been L for the condition you described. Or Logically It will be activated at M and then RC= MMC+GTOL+Bonus. Which means when the shaft is biggest it should be centred as it will be hard to insert.
I don't understand what you explained. Shaft RC = LMC - gtl - bonus. Hole RC =LMC +Gtol+bonus.
@@TheEssenceofknowledge For the shaft you have to look at the worst possible condition. That would be shaft at its biggest, when mating with the hole it will have issues as a small shaft will fit ... a big shaft won't fit. Which means
Worst case scenario = MMC of Shaft + True center of the shaft is displaced.
If the true center is displaced, that will result in an effective diameter of 0.1+0.1 when the shaft is moving (you can look at it from a Gaussian curve or from 2 point method... )
So True center will only be activated when M (M here stands for MMC according to the notations) is met .. which is the maximum material condition of the shaft.
So now the worst case for a moving shaft in a hole is :
Worst case scenario = MMC of Shaft + True Center offset (0.1)+ Bonus when moving ( 0.1)
@@Darthvader81498 yes correct worst case is VC. That do not carries bonus. Bonus is the case when MMC modifier is in Gtol frame. So virtual condition is VC=MMC +Gtol for shaft. VC= MMC-gtol for hole. No bonus is in VC. RC is best case. Bonus we get when manufactured dimension departs from MMC towards LMC. And bonus is equal to amount of departure. RC is best case when shaft or hole is at LMC. RC= LMC-GTOL-BONUS FOR SHAFT. =LMC+GTOL+BONUS FOR HOLE. This is as per ASME 2009 Y14.5. let me know if this clarifies you.. thanks
@@TheEssenceofknowledge best case scenario kind of defeats the purpose of stackup analysis. Also when the GD&T box has M it is only applicable during MMC. M modifier means MMC
@@Darthvader81498 not only applicable to MMC, it is thru out. That gives Bonus. It means, if shaft manufactured at MMC we get only Gtol mentioned. But if manufactured dim departs from MMC we get bonus of amount of departure as a form or position error that is allowable. at LMC we get max bonus. Now if someone uses LMC modifier L in frame concept reverses and we get bonus when dim departs LMC. The formula and the concept is from ADME2009 Y14.5.
Nice video...clear understanding...
Thank you! A quick question from 12:42 to 12:50. Shouldn't the re4sultant condition be MMC-GTOL-BT instead of LMC-GTOL-BT. In tha case your shaft becomes 9-0.1-2 = 6.9mm. Shouldn't it be MMC-GTOL-BT which would be 11-0.1-2 = 8.9mm?
If mmc modifier is in gtol frame, RC is always based on LMC. MMC will be in calculating VC. RC for a shaft is at smallest sizen of shaft and considering hole where it is assembled is at true position and at biggest size. This LMC - gtol - BT does not imposed on size tolerance zone. Do not confuse that shaft can be manufactured at RC, in manufactured dimension limits of size always respected. Let me know if this answers your question
if the parts get manufactured shat at lmc the bonus tolerance is 2.1 corect ?
bonus would be MMC-LMC only. The RC = LMC - Gtol -Bonus for shaft, = LMC + gtol + Bomnus for hole
Nice One Sir.👍🏼
It was an informative lecture
You say 2mm for a bonus tolerance it is a difference in diameters but you highlight a difference between radiuses which is 1mm, is that correct?
Bonus is actually variable should be referenced to manufactured dimension. Bonus is MMC-manufactured dia. In case it manufactured at LMC.. we get 11-9 that is 2 mm. Let me know if this clarifies.
Nicely explained
Sir presentation last line u said bonus tolerance which is MMC-LMC then should add tolerance also I think please correct me if I am wrong
Bonus is like additional tol for positional error we get. If part is manufactured at MMC we get the Gtol mentioned as positional error. But when it departs towards LMC we get bonus of amount of departure. When it is manufactured at LMC we get max departure that is MMC-LMC. So that is best case bonus. Let me know if this clarifies your query.
Obrigado aqui do Brasil!!! Grande abraço !!!
obrigada tudo de bom
Explained well. Thanku
Hi,
Vc for shaft is min hole dia req to accommodate the worst case senerio of the shaft not the max hole dia...
Hi, yes correct. I think this thing we discussed before 2 month as well. Next lecture includes that. And while explaining I was thinking of shaft so gone this way.
And please keep exploring and let me know. Thank you!!
Sir, where is stack up lecture 2 and 4, I know you have uploaded those two video but right know they are not showing in channel
Hole dimension is dia 10 + or - 0.5 ,I need a transition fit . So wot will be the size of the shaft and tolerance
Transition fit toleraces are generally too precise. Here tolerance zone is. 5. Study bearing for transition tolerances. Skf provides good detail. Like 10 mm, keeping 10 as base bore tolerance should be - 8 micron to 0 micron. Shaft can be h6, h8, j5 or j6 depending on condition and requirements. Let me know if this helps and your further queries
@@TheEssenceofknowledge Thank you sir
THANK YOU!!! God Bless you!
Sir, please make video on how to calculate or how to decide limit value (upper and lower limit) for any dimensions of any part.
It's always functional requirements of assembly. In some cases positional tolerance can be calculated..
Nice explanation
Sir, Please explain me how this affects a production and do some numerical calculation
This affect design, if we do not do Tolerance analysis. We might get component got manufactured but causing problem during assembly..
Thank you sir.....
What are you teach I understand....
But my doubt...I will make one shaft(DIA 5) with assembly, shaft will come MMC=6 , and also hole will come MMC=4, How to assemble that part.
if you make shaft of 5±1 its VC = MMC = 6. Always hole vc should be equal or greater than shaft vc i.e. hole VC = 6 = mmc of hole. Now we know hole MMC = 6, Hole LMC = MMC + tolerance, suppose tolerance is 1 so lmc hole = 6+1 =7 so hole dimension must be 6±.5. this is how it goes. let me know for further clarification. Thanks.
@@TheEssenceofknowledge So here in a condition of shaft and hole in MMC, how can we assemble? As you said, Shaft MMC = 6; Hole MMC is 5.5
@@narenmids sorry for late reply. I have said hole MMC 6. So it cant be 5.5 it will be more then 6 always. Let me know if I am not getting you correctly. Thanks
does modifier "M" add bonus RC only for Least Material condition? Is there a modifier available for MMC ?
Modifier m means that the MMC is important and gtol is applicable if part manufactured at MMC. If manufactured size departs from MMC we get bonus of amount of departure and Max bonus is available if component manufactured at LMC. Modifier M is for MMC showing it is important. Modifier L shows LMC is important and we get bonus when size departs to MMC from LMC. Let me know if this clarifies. Thank you!!
In the above example, the Bonus tolerance is 1, or is it always the difference between MMC and LMC irrespective of the hole or the shaft?
for calculations yes. Actually the Bonus is amount of departure. Suppose Shaft manufactured at MMC will get 0 bonus, If shaft shaft manufactured departs from MMC towards LMC, we get actual bonus as amount of departure. Let em know if this clear.
ohhhh well explained !! Thank you so much
thanks
I LOVE YOUR TEACHING STYLE BRO
Nicely explained , Thank you
Thank you and welcome.
good explanation
Hi Sir, I have a doubt what is the use of Resultant condition in Stack up Analsis
sorry for late reply, I was travelling. by calculating VC and RC we get a single size and tolerance replacing size its tolerance and GTOL. that we can use in stack-up. please let me know if this clarifies.
@@TheEssenceofknowledge No Sir, Please explain me how this affects a production and do some numerical calculation
For RC condition of shaft ,
Why do you need to add bonus tol... logically if you consider virtual condition at LMC(THAT IS LMC+GTOL) for resultant condition,Then it's very much looks logical and acceptable right.....
I know it's written in book.but by which logic we are adding bonus to it....I want to say you add LMC & GTOL ,I am ok with that but why adding BONUS TOL alag se....please explain the logic behind it but please don't quote lines from book..
Hi Saurabh, I never used a book. The things I have explained in here are always from my 11 years of experience and ASME
Do you understand what Bonus is? Suppose as a designer for a shaft MMC is critical to me as per assembly so I have given MMC modifier in gtol frame. That allows a manufacturer to have a form error of gtol + the amount of departure from MMC and eases manufacturing processes. That is why we add bonus. Please watch couple of lecture from my GD&T sessions it will clarify more. Let me know if this helps.
I have learned that Bonus tolerance is the sum of (difference between MMCwith the actual condition ) and the GTol ?? Is that wrong ?
ajun susekh, Bonus is difference between Mmc and actual manufactured..I.e. departure amount. Gtol is always there.
Hi, in bonus tolerance of resultant condition for the given example is 2.1mm or still .1mm. Please clarify.
Bonus tolerance is the amount of departure from MMC. Suppose a shaft 10 +-1. And gtol of.1 and modifier is mmc given in frame. If shaft at its MMC that is 11 we will get no bonus. Now suppose shaft manufactured at 10, amount of departure is 1 so bonus will be 1.0 and gtol is..1 so total tolerance 1.1 now suppose it is at 9 i. E. Its LMC for resultant condition we get max bonus of 2, this is amount of departure and gtol is. 1 so total tolerance wll be 2.1 at resultant condition. Let me know further query. Thanks
thank you so much.. i was stuck here
Hiii sir,I saw ur lacture vedio it is very helpfull for me,so thanks for u, I want to know about how to relate flat tolerances to the position tolerances on same face.
Karan, not sure in which ref you are asking but position will control it location with respect to a datum where as flatness contols form means surface lies between two parallel plane irrespective of any datum. Let me know ur further query. Sorry for late response
Sir even if u consider RC, Should the Gtol be positive? like RC=LMC+Gtol, bocoz u know if whatever way it shifts then that much dia of hole is needed to fit right?
It is inside boundary so should be substracted.
@@TheEssenceofknowledge TQ sir. Sir can we expect full course on GD and T form u. It would be lot helpful for us🙏.
@@sureshpadasalagi7112 I do that. Next Batch is coming on 20, that is a weekend batch. Saturday and Sunday
@@TheEssenceofknowledge Do I need to register for it or it will be on CZcams for free? Sry for lot of questions I'm new to the channel
@@sureshpadasalagi7112 it's paid and need to register.. thank you Suresh
best video for mmc annd lmc\\
Thank u so much for ur valuable lecture...
Excellent explanation Resultant condition not understand
For a hole if MMC modifier is used, the Resultant condition is when hole is produced at biggest size that is LMC and it is dislocated by Gtol and bonus. It will be LMC + Gtol + Bonus
Good one, but I think gtol should be taken half of the tolerance given
No, it's Gtol. Because that is available at RFS. Refer ASME 2009 Y14.5
Hello sir, my doubt is what if I use L modifier. The vc is a worst case or best case. Plz explain vc & rc for lmc concept
See lecture 10 of gd&t. It explains it.
Good explanation
Dear sir ,we have required clearity shifting of shaft which side
I think it can shift in any direction with in gtol value. Please let me know if you are asking questions un different context. Thanks
Position tolerance will usually be symmetrical tolerance but you are explaining it as tolerance applied in single side of the shaft ... Correct me if am wrong
Positional envelope will be a cylindrical one, so it is always symmetrical. But In real case shift is posible one side only at one time. That is why I am explaining so. Formulas are correct, you can see images in video or refer ASME 2009. Let me know if need more details.
good one bro.....
Nice explanation & easy to understand, if possible can you please give the same example with position control (GD&T)
naveen kumar , yes sure..
Tq sir.. It is wonderful explanation..but, I have a doubt in this lecture that what will happen on both shaft and hole if we given lmc modifier.. Pls kindly explain this doubt sir.. Tq..
With LMC modifier the LMC condition will be important and we get Only mentioned Gtol.. as component departs towards MMC condition we get bonus. I have explained in one of the video. Thank you!
@@TheEssenceofknowledge share the link of that video in comment
Sir what is the use of VC ?
Very nice....
Sir.
Please explain me about Bonus Tolerance and its modifier.
Okay, I do online classes, whenever the session will happen I will let you know.
@@TheEssenceofknowledge ok sir.
this is so perfect thank you so much sir.. and hats off for sharing your's wonderful knowledge ...
Thank you.
Sir, in this video you were said if Gtol got (M)modifier there the shaft will manufacture smaller.here my question is if Gtol got modifier (L) what will happen.
More over here as per the RC formula the shaft dia get 6.8 (LMC-Gtol-bonus.9-0.2-2=6.8). But the shaft LMC is 9. Here the shaft dia-6.8 ( as per the RC formula) this 6.8 dia is so exceed the LMS dia 8.is it possible?
Would you please check lecture 10 in gd&t. It will help for that. Let me know further queries. Thanks.
@@TheEssenceofknowledge can I get the answer for my 2question also in lecture10 video.
@@vijayg1776 the answer for that is cross sectional size must be with in size tolerance limit. Suppose a shaft 10+-1. All cross ection must be between 11 and 9. But suppose it is distorted all the way in lenght by 1mm it will have envelope of 12. Mini size of hole will be 12 because of form error. VR and RC are virtual effect of form errora. Size tolerance must be respected everywhere.
6.8 is resultant condition boundary not diameter. It like common boundary of shaft manufactured at LMC and displaced by given gtol and bonus in all directions.
Sir, Once we are calculating VC & RC of shaft, how decide the counter matting part hole Nominal dia, hole feature tolerance and position shift.?????. Thanks in advance.
KARTHIK Ramasamy , the virtual condition of shaft should be virtual condition for hole. Once you calculated vc of shaft you will know what minimum hole dia you need. Then depending on fit needed decide dim. Suppose it's a dowel pin hole, you should select transition fit.
Let me know further query
I have just started with the whole understanding of this GD&T and thus have a question regarding it. What are the different types of GD&T courses do we need to study in order to study this whole subject? I guess Stack up terminologies are one of them. Can you name the rest? Thanks!
Refer ASME 2009. Y14.5. It shows Dimensioning and geometric tolerances for drawing. Stack-up is study of tolerances. Similar things are like DFMEA, SIX SIGMA etc. This will be enough for defining a geometry on drawing. You can learn CAD, FEA software to enhance further more on design side. Always keep basics of design with these skills. Let me know if more queries. Thank you.
Oh yes, this makes sense. Thanks!
what is the impact of modifier M in bonus tolerance sir?
More usable parts those might be rejected due to stringent Torrance will be getting accepted after using this.
What is GTOL
Geometric Tolerance
Sir pls clarify my boubt sir, we calculating virtual condition of shaft..reason for..minimum size of hole to accommodate the shaft, it is reason for calculating virtual condition. But resultant condition, we are calculating for shaft ..why are calculating..what are types of reason. Can you please elaborate explain this
Many time loose fit also may result in many issue. So we calculate RC. That is why RC and VC used in tolerance stack up analysis to get max clearance and min clearance or interference. Let me know if this clarifies. Thanks.
Thank you very much sir for clarifying my doubt sir.as your brother I am asking sir.why your don't put more vedio...
@@vijayprakash8666 thanks Vijay. Last 8-9 months never been easy for me. Was dealing with few bad things. Now bad phase over. Planning to new start. Soon will be back. Thanks Vijay.
@@TheEssenceofknowledge .thank you for your reply sir.waiting for u vedio sir.not only me, many people eagerly waiting for u r vedio, pls as soon as possible putting vedio..your explaining spr sir, easy to understand sir..
Sir can you pls share material , my mail id vijayprakash305@gmail.com
best lecture !!
If bonus tolerance applied. R.C for hole is 13.1.how it is
I m not sure at which point you aking but RC for hole is lmc + gtol + bonus. And bonus is maximum amount of departure that is LMC of hole - MMC of hole. Please let me know further query
Is there any certification programs available related to GD&T?
You can get certified from ASME
How to deduct bonus tol. From shaft what is size after deduction please clear
Bonus tolerance is only available during best condition that is at resultant condition when shaft become smaller or hole become bigger. Suppose shaft size 10 +-1 so when it get manufactured at 9, we get bonus of 2 and deducted while calculating resultant condition.
How to calculate the tolerance stackup of hinge button to press micro switch? Or give example for rotating parts say 5-10 Deg.
I have not much Idea regarding hinge buttons.. I will check and get back to you. If you have any rough sketch of parts I can guide better. If we are doing stack up for polar dimensions, all dimensions should be in that or we will need to convert them in linear form.
@Kate Jayesh please share any image or any thing for reference on which I can do analysis. Mail Id bipinkumar.SinghLNT@gmail.com
I have this question from my work. A dimension of a part has a position tolerance of 0.35 mm. Inspection report from supplier says 0.470 which was accepted and in comments he said "according to MMC up to 0.555". My question is bonus tolerance is applied only to hole right? or also for position? How can position tolerance be 0.555?
sasi r, actually bonus tolerance applied only when modifier MMC is in gtol frame. Suppose your dimension is 10+-1 and gtol is given of .35 with MMC. It means when dimension manufactured is 11 that is MMC you will get only position tolerance of .35. but now component manufactured at 10 that is departure from MMC is 1 mm, in this case you will get 1.35 mm of position tolerance. And now suppose it get manufactured at 9 that is it's LMC, Its departure from MMC is 2 mm you get position allowance 2.35 mm. This additional we are getting is bonus. I explained you for shaft or block. Same will happen with hole or slot. Bonus is applicable to all dimensions if gtol has modifier.
Let me know if you have further questions. Thank you. Watch GD&T session it will get more clear..
best lectures thanku
What will happen when MMC given to the datum also ?
That is not MMC. That is MMB. In that case datum simulator will be maximum material boundary.
@@TheEssenceofknowledge I have read one control frame in which datum given with MMB and also with plus and minus some tolerance ?
What will be it's meaning
@@unstoppable1808 that means the value of datum shift allowance. Check my video on Datum shift.
is there any online course on tolerance stachup
There are many, I am also coming with that soon.
WHAT IS GTOL???????????????????????????
Hahaha.. my way of refering geometric tolerances.
What are the types of tolerances in gd&t in general sir.
GTOLs mainly grouped as form, profile, Orientation, Location and run-out tolerances. Watch GD&T lect 2 for brief of gtols.
Sir, How it is find out in drawing(Virtual,Resultant condition)?
You can calculate with these formula, reference from ASME 2009 Y14.5. If no Gtol, worst case will be VC and best case will be RC.
Hello sir ,
Thank you very much.
Do you have any channel in telegram??
Please post the link.
I have not much knowledge of telegram. Please suggest so i can do same at there.
On telegram you can keep us updated about new video and ask us to vote for on which topic video should be done!
Pls share your comments on rc and VA.
How to calculate tolerance for runout
Ram Kumar , I will cover details about runout in GD&T lectures, but the value of tolerance is always a functional requirement. Suppose we need a very fine gap, than based on stackup analysis tolerance value will be decided. Let me know if you have any specific case, I can guide you for the values.
Difference between MMC and virtual condition. Please answered me. And what is GTOL
Amardipsinh Rahevar , MMC is Maximum material condition, Gtol is geometric tolerance. MMC for shaft or hole is when feature will have maximum material where as virtual condition for a shaft is minimum size of hole required to accommodate it in its worst case. What is worst case for shaft, when it is at MMC+ position or form error of Gtol. Same way for hole virtual condition, max Dia of shaft it can accommodate in its worst case. What is worst case of hole, it is it's MMC - form, position error(Gtol).
Amardipsinh Rahevar , please let me know if further queries.
G.TOL?
Thank you for the info..
Sir why we need to calculate virtual and resultant condition?
We calculate VC and RC for considering effect of geometric tolerances during stack up analysis. Let me know your further query.
How
@@deepakgarg2953 please see lecture 6in this series. You will get answer. Let me know further queries.
thank you
I have doubts for vc and rc.
Hi Snehal, please tell me your queries. You can mail me those on bipinkumar.singhlnt@gmail.com