Everything DIY mechanics don't understand about bolts | Auto Expert John Cadogan

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[@AutoExpertJC]

OLIGHT Sale! (These torches are awesome.) Sale ends midnight Wed 23 Aug 2023 bit.ly/3zF5hCQ Swivel Pro Max, up to 35% off: www.olightstore.com.au/s/LYXPV4 Warrior 3s Black Stone Wash, up to 35% off: www.olightstore.com.au/s/P7IGZD I5R, up to 35% off: www.olightstore.com.au/s/BW5YW5 Baton 3 Pro Max, up to 40% off: www.olightstore.com.au/s/E9Q1BM Freeze 3 Damascus, up to 35% off: www.olightstore.com.au/s/GHBGLX Exploit Mini, up to 35% off: www.olightstore.com.au/s/1CMLVF I3T, up to 35% off: www.olightstore.com.au/s/06MV27 Seeker 4 Mini, up to 40% off: www.olightstore.com.au/s/E6STDP Seeker 3 pro, up to 40% off: www.olightstore.com.au/s/XPHNW0 12% off after the sale: Use code AEJC

[@damodoesall6240]

Will the magnets work undr a wheel arch?

[@JAStheACE]

It would need to be a wheely big arch. @@damodoesall6240

[@cunning-stunt]

What about the alloy wheel bolt seat? That will deform long before the bolt will yield or reach it's proof load. I have seen bolts wound in so hard that the end of them were clipping the shoes inside the brake drum. The bolts were fine and they were the correct ones for the car.

[@robertveldman1901]

Nice job. As a retired suspension engineer, I saw you touch on most factors concerning threaded joints. In automotive land, over torquing is a big concern, not necessarily for breaking fasteners, but for distorting or breaking the mating parts. It's amazing how far you can draw a taper bolt thru an aluminum suspension part with an impact.

[@randyhanson837]

I once had a new hire kid (machine shop work) tap a part completely through the part. As I asked him "what were you thinking" he excused himself by saying "well it did seem a bit difficult to get through". It was a clean thread, so I had to give him credit for that LOL

[@kriskabob]

I agree that with wheels, the torque spec is generally for the rim and not the bolt, which is why steelies have a different spec than aluminum, and I'm assuming different than high end mags, all on the same vehicle/bolts.

[@dudeonbike800]

Once WheelWorks broke my second Toyota wheel stud, I never returned. You have a few jobs, with ONE being: to put wheels on cars safely, efficiently and effectively. And you can't even do that.

[@sidserv1978]

I am a retired aircraft machinist/welder. After 20 years of doing that I decided to retire. I got bored so I started driving school bus. Then the mechanic quit and I was asked to fill in. After 6 months of that I became the head mechanic. It is amazing how many people use German torque or guudentite. I am glad you are bringing this up. It is a great topic!

[@mtdm8233]

As a full time automotive tech i have had the argument on why torque specs are important with even master ase techs. It blows my mind how dismissed this has been. If you really want a hoot tho bring up why different coolant and coolant specs are important.

[@beardedgaming3741]

i bought a set of quality torque wrenches. its amazing just how many people shrug those off, give it the 'what ever' torque and ship it.

[@jamesk7446]

@@fastbusiness - you would be surprised how accurate an experienced mechanic can be by feel. Typically 1/4 turn past sharp rise will put you right in the torque zone of quality high strength AN spec hardware. But - if one gets lazy, that feel can easily yield non-hardend steel bolts and anything that runs into aluminum.

[@crackpotfox]

​@@fastbusinessIt's incredible how few people take pride in their work and do the job correctly.

[@beardedgaming3741]

@@fastbusiness I watched a video where they got a bunch of people, mechanics and engineers and from a bunch of different aspects of the fields. They tested them, having them torque bolts to what they thought was a certain foot-pound. There was one dude out of like 25 people they got who nailed the torque specs. He wasn't even a mechanic, he was a applied materials engineer or something like that.

[@malcolmduncan3047]

Good job, John. I could not fault your tutorial...from a 75 year old retired fitter/turner/welder, engineering technical officer, mechanical engineer.

[@bonza167]

ditto for me too, except I'm 69

[@richardwalsh5570]

Ditto me too 57

[@mrrberger]

Hmm, what about the torque wrench accuracy? should have been 14nm not 7 as it's plus minus 4%. Or for you fitter/turners, wasted shank studs where the shank diameter is smaller than the thread root, last century technology auto engines (except Broadmeadows Fords Mal) with exactly these fasteners as standard, doing a nut run test shows nothing of plastic elongation. Then there's the load distribution across the thread lands, each thread takes less load the further into the clamping material. Ad to this lubrication squeeze out that's time based and to much or thick lube, holds up the bolt washer face and thread clearance until it bleeds down. A one pull torque back shed engine builder wont be anything like close to 35%. Using a length "stick" with tape to indicate load values was an interesting choice as many would "monkey see, monkey believe, monkey not listen" that the example is load value not stretch displacement. Bet many watchers without the colourful career you espouse would hold their hands apart if examined on their understanding.

[@Chris-sf2cp]

I think you made that comment to blow smoke your own ass. Look everyone look how “ important “ I am I need to tell everyone about every single job I have so that I can feel good about myself.🤡🤡🤡

[@chevalsauer]

I've seen him do some serious physics calculations that would do any physics teacher proud, it was on the calculation of a specific European car towing a 747 I think... all filming done in closed quarters incase it pooped its pants on the actual pull... review 😆 🤣 😂 never forget that one!!!

[@christophermarshall5765]

One place I worked at had a customer come in with his car on a tow truck. Only problem was flat tyre. Big problem he had was not getting the nuts off to put the spare on. New tyres were fitted a week prior, & the nuts were done up to the point they bound on the studs. Spent time drilling the nuts off, removing the wheels, & replacing the studs & nuts.

[@estosgarage486]

Excellent real-world examples. The young techs must see this !

[@AutoExpertJC]

I agree - all the world must watch!

[@mrrberger]

😂@@AutoExpertJC

[@stephenshields1662]

I buy from Bolt & Nut Aust. , great to deal with. Love these tech videos, plain English and informative

[@bens5186]

Mate… it’s not just DIY mechanics that have issues with this. Go to any mining or oil and gas site you will find at least 1/2 the fitters under 40 have no idea about fitting fundamentals. Flange fasteners being flogged up past yield often…. “I have flogged it past yield and it’s still leaking… guess I’ll flog it some more.” /facepalm Great presentation.

[@AutoExpertJC]

I agree, and thank you. There are butchers and cowboys everywhere, of course.

[@Low760]

I've seen it too much in places it shouldn't on trucks.

[@mickmcgillicuddy5437]

Good work John. I've been selling and designing fasteners for 40 years now, and what I still love is to wind a good fitting nut up a thread. Endless mindless fun. I have some go/no go nuts for special studs and such and there is no better feeling than running them up and down the thread. Cheers

[@tundramanq]

My favorite peeve is over tightened oil drain plugs. The oil pan only has 5 to 7 threads so the expensive and hard to replace part is the oil pan and not the bolt. Seen this on oil filters with side o-ring seals on plastic housings also. Quick change oil places will hire off the street minimum wage kids with no proven experience and turn them loose on customers autos.

[@Slicerwizard]

Yep, the one time I didn't want to change the oil in the driveway in the middle of the winter, the quickie lube rounded the drain bolt head - obviously used a too-large socket. At the next oil change, I had to remove the bolt (and reinstall it) with vice grips. Replaced the bolt on the following oil change. Never again!

[@cengeb]

Never use quick change places,cus now even dealers will do quick oil changes,with no appt. Even drain plugs are plastic,and the oil pans..never over torque. Oil canister housing plastic, reason why they give torque specs

[@TheCharacter97]

A year ago or so we bought my wife a "new car" (had 48 000km 2018). Well I do all the car maintenance that I can so obviously oil changes are a no brainer (been doing with my dad since I was 10 years old). Well first oil change comes up and the oil pan plug was so damn tight they crossthreaded the bolt and pan threads.. I wanted to buy a new bolt at first but then thought the pan threads are crossthreaded as well so might as well keep the matching threads with the bolt.. It sucks because the car only had 48 000km when we got it and was getting things done at the dealership..

[@StrongerThanBigfoot]

@@cengebYou don’t even need to torque it just hand tight snug

[@grilsegrils9330]

I had an old Toyota, and tried to save a buck getting the wheels changed by these foreign ghetto pop up shops (Pakistani maybe). When I saw him put the jack on the sheet metal surfaces under the car I cringed, and never went there again. So yeah

[@LTVoyager]

Nice video. The only things I noticed missing was a demonstration of using a torque wrench properly and a discussion of static vs dynamic friction and its impact on torquing fasteners. Many don’t use the torque wrench in one smooth and continuous motion, but rather tighten almost tight enough and then either ratchet the wrench or reposition the socket due to not allowing enough swing to complete the torque process in one continuous motion. Knowing the difference between static and dynamic friction helps folks understand why torquing to within 20% or so of final torque and then completely the process in a second swing can result in substantial under torque if the additional force applied isn’t sufficient to overcome the static friction.

[@Pocketfarmer1]

So what do you do when there isn’t enough room for one smooth swing?

[@LTVoyager]

@@Pocketfarmer1 Set a torque value of about 60% of the desired value and tighten there first. Then set the final value and finish off. The key is to stay well below the 80% mark on the first swing so that you will be sure to exceed the static friction threshold on the final swing.

[@fantabuloussnuffaluffagus]

Unless the torque wrench clicks without moving the fastener at all on the second pull, no matter how short the pull, both pulls involve kinetic friction.

[@LTVoyager]

@@fantabuloussnuffaluffagus True. It can be hard to detect a slight motion with some wrenches. Good practice to mark the fastener to ensure it has changed position. Better to use good technique to start with.

[@antilogism]

I might add a demonstration illustrating that bolts are springs, so that the need to be sufficiently tight becomes very clear.

[@johncooper4637]

Here in USA there is a book by Carroll Smith called "Nuts, Bolts, Fasteners and Plumbing" that has excellent information. One of the downsides of regular fasteners is getting the right thread length so the threads don't impinge on areas they should not. For non metric threads my solution is to use Aircraft Spruce and order AN fasteners where the non thread portion is in 16ths of an inch. This is very useful on formula cars where there are a lot of spherical rod ends. There are a lot of broken wheel studs on heavy (semi) trucks because the mechanics are using a 1500 ft. lb. impact gun on a nut that is supposed to be torqued to 500 ft. lbs. My motorhome on a bus chassis requires 500 ft. lbs. of torque on the Alcoa wheels with correct lubrication.

[@2shay550]

I was a medium/heavy truck tech for 16 years and can't say I've seen more than a few broken wheel studs. Most were caused during removal or installation. But, I was a dealer tech and we didn't do tire work. Plus one of the shops I worked at was a stickler on torquing lug nuts. Personally, I never trust an impact gun on any component that could cost someone their life.

[@klo1679]

I never saw a broken wheel stud on any trucks due to overtorquing via rattlegun, considering we never used a 1’ drive 1500ftlb gun. We only ever use a 3/4” Milwaukee to run them in, without going full ugga dugga

[@frederickburns1739]

Well done John!!! I use Never Seize on the majority of fastners and a while back had to explain to my tire shop guy the reduction of torque when using Never Seize.

[@winnebago2]

I started using anti-seize but didn't think about the torque reduction, how do you estimate the reduced torque?

[@randyhanson837]

I think it is because of the lubrication makes it easier to turn/tighten and distorts the actual stretching that is what torque is meant to measure. I just read what I just wrote and now I am confused too.

[@Deere2154D]

​@winnebago2 should be able to look up wet torque vs dry torque for desired bolt size

[@1hendo208]

That was awesome. Totally explained what until now was a mystery. Thank you.

[@AutoExpertJC]

My pleasure - thanks for watching.

[@moogz2478]

Screw clamping force does affect the material it’s clamping too. For example, on a crankshaft bearing cap, over tightening compresses the grey cast iron and reduces the top to bottom oil clearance. In one example I’ve done, an increase of 25Nm to a 100Nm crankshaft cap screw reduced the 20 micron oil clearance to zero.

[@Born_Stellar]

I assume this is why for some high powered engines you use a thick bracket on the head when milling the cylinders. clamping the head down slightly effects the shape of the bore.

[@donaldthomson8965]

then there is something wrong there some one been grinding your caps id bee checking see if caps are flat

[@MrTheHillfolk]

​@@Born_Stellar and that's also why you get the rod end resized when you go with aftermarket fasteners like ARP. The torque on the bolt might be different than the original, the thread pitch might be different, so your clamp load on the rod has changed.

[@dillpickle7468]

Great video JC, informative as always. As a DIYer with no engineering training, this was a very helpful. Thankyou

[@rodbennett4790]

G'day John, I'm impressed on this my first visit to your channel. You've touched on a topic that is close to my heart, as I produced a book on Threads and Bolting before I retired. As you know, like with everything, there are things you need to know about bolting if you're going to do it properly. We use the expression of getting down to the nuts and bolts of something, implying that nuts and bolts are so simple. It turns out that the nuts and bolts of something aren't that simple! One of the things that works in our favour when we just tighten a bolt without considering its tensile strength is that the Modulus Of Elasticity is practically the same for all tensile grades. So, if you tighten a high tensile bolt with the same amount of "feel" as garden variety bolt, it will probably perform just the same since they both have the same amount of stretch. The problem comes when the high tensile bolt doesn't have enough tension to hold the parts together in service. If you're bolting together a bed frame or gate, etc, it doesn't matter too much. Anything more important (e.g. an engine) requires a torque wrench and torque tables (torque tables are a topic all on their own!). For safety critical applications such as pressure vessels, cranes, etc, it is essential to use the manufacturer's specification or have an engineer do the calcs. Torque table simply will not do here! There's much more to cover on this topic, and I know you know this stuff, but I comment here for the benefit of those who don't. I'm impressed with the organisation of your shed. A man after my own heart. I did notice a flogging spanner in the background. Not much torque control there! For demonstration purposes only? Great work. I've already identified a bunch of your videos that I'm keen to watch. Thanks for the excellent, professional presentation. You're very good at it!

[@JeffreySchellenberg]

I was an aircraft mechanic and just recently switched fields to wind turbines. I'm interested in reading the book you wrote. Can you tell me the name of it or where I can find it? I wasn't able to find anything via my 25 second google search lol

[@rodbennett4790]

The book was produced for internal use by the company I worked for. It was not published and unfortunately is not available. @@JeffreySchellenberg

[@denisturcott5131]

Very good info for all those that work on machinery of all kinds. I was taught that when putting a bolt into a blind hole you must tighten and record the brake off torque and repeat until all bolts are within a few foot pounds.

[@BrandenBrashear]

I use "freedumb" units, but your use of proportions made this simple to understand, thanks!

[@LogicPTK]

Appreciative of the depth of explanation covered here John, very thorough and understandable.

[@dawayneduffy3509]

Great video mate. Much appreciated that you take the time to show us this. Keep up the awesome work champion.

[@GrahamGrumpy]

Well done, clear and concise...from an old design engineer qualified to torque high pressure steam joints.🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@trevorreeves5041]

The whole series on Bolts/fasteners & torque wrenches is a great primer for the old and new of us. Thanks J.C.

[@Blanchy10]

In the 80s I worked for a local mechanic. A certain Japanese Manufacturer that started with M seems to have had a problem with wheel studs. Service time for these vehicles would see multiple broken studs to the point where they were kept in stock.

[@LordSandwichII]

Mazda? Mitsubushi?

[@Blanchy10]

Mitsubishi@@LordSandwichII

[@johncoops6897]

The reason that happens is that almost ALL mechanics use a rattle gun on wheel studs/nuts. Most of them use a rattle gun on oil pan drain bolts as well... they aren't usually employed as a car mechanic because they are intelligent or give a st!t about their client's vehicle.

[@Blanchy10]

Only happened to one particular brand of car though. The mechanic I worked for used a Torque wrench on those cars because of how many came in missing studs.@@johncoops6897

[@SLOCLMBR]

​@@johncoops6897sad but true of lots of lube techs

[@deltorojoeysativa1558]

I just love that i finally found you. Thankyou for your time and energy.

[@Harwar1976]

Great video and very well presented John. Particularly enjoy the engineering perspective,under appreciated by us mere mortals. Thanks for doing these informative videos. Your sense of humor helps too.

[@frozendude707]

Now this is what I needed but did not know I needed, I have been wondering about what makes a torque spec and how different assemblies could need different torque to fasten, and this explained it plainly and beautifully for me. Bypassing the maths formulas for your mental model and comparing it with units most can understand intuitively was genius.

[@tfm1449]

Wow, my hat is off to you sir. This technical dive you have taken us to is outstanding. I have been a professional maintenance mechanic for over 30 years. I have tried to educate the DIYer on this subject many times, only to get a distant stare. Some people don't understand why there is such a big deal about this.

[@ianbelletti6241]

Torque specs are there for at least one of two reasons. 1) to prevent loosening of the part especially higher torques where it's hard to tell if you've met or exceeded the torque value. 2) to prevent part damage. Some cases may be both. However, most situations will be one or the other. For part damage it could be the threaded parts but it could also be the parts that you're assembling with the threaded part.

[@Deere2154D]

Depends. You forget about torque to yield or torque stretch bolts.

[@MrSky084]

100% agree with your comment about Bolt & Nut Australia. Needed some weird sized rivets for a job, couldn't find them at my local Bunnings and found this company online. Fantastic service, got the required rivets in 2 days!! Brilliant. I will use them again.

[@scottouimet2865]

A few of your videos have come up for me on torque and torque wreches etc and youve taught me alot that i didnt know about using an important tool. Thay was maybe not so important on the older cars ive worked on but definitely the new ones

[@SANDSCORCHER]

Thank you John😎👍🏻 Another superbly illuminating and edifying video in equal measures, for both the layman or an old hand.😎👍🏻 Well over thirty years ago, a couple of my college lecturers could have used a lesson or three in your style and approach to disseminating vital yet complex information to those that need it👍🏻

[@williampezzner4229]

Hi John. Thank you for this video. Really very helpful. Semper Fidelis.

[@farken7467]

Great video John. I must agree that Nuts & Bolts Australia are brilliant as are Automotive Superstore, especially for those of us tired of Repco & Supersteal. So much of this stuff I was shown by my screaming father as a kid. Thanks to your style John It's now making sense in a way the old man could never achieve. Much appreciated.

[@TheComputec]

Thank you for this brilliant information John. Never had these things explained so well in all of my years.

[@cleanmachine08]

Great video. Bolt & Nut Australia have been consistently awesome for all my orders over several years. No matter what complicated assortment of random stuff I ask for, they've not put a foot wrong!

[@samrodian919]

John that was so informative! Thank you so much. I'm the guy without the bone through his nose who has never used a torque wrench in his life for wheel studs, just a two foot breaker bar and maybe having to stand on it to get the nuts ( or bolts) undone but only ever using moderate body or leg pressure to do them up depending on size of vehicle( inc Land Rover forward control models ) being around 16 stones ( old school UK measurements here lol) or 101 KG and never stretched or damaged a thread on a wheel application in more than 50 years of spannering. I did and do use torque wrenches for engine work or suspension safety stuff. I'm just about past my yanking on spanners, (I refuse to call them wrenches!) so I won't have to get my torque Spanner out any more, but if I were to do that I'd certainly use it as long as I can get the figure in foot pounds because my torque you know what is calibrated in those imperial measurements. Great video mate!

[@dirtlifestyleoz8150]

This is great, going through use of torque wrench with my son this weekend, this will be very useful considering i can explain it this well, thanks John.

[@s2t4i6n9e]

That's one of the most well-presented explanations of bolt torque I've seen since the days of Compuserve. Well done!

[@hootinouts]

Sir. you covered this subject superbly. I have been doing my own automotive maintenance for over 40 years now and I always use a torque wrench on critical fasteners. I always torque the OEM fasteners to the manufacturer's spec. Also, I am a machine designer and I always specify torques on fasteners on the drawings I generate.

[@GW1957-SY]

Thank you John You have transported me back to my apprentice days back in the 70’s in a British Leyland dealership! Great stuff

[@angusmacmillan5365]

Brilliant video! I've often wondered aboput all this. Thanks, John.

[@alext8828]

The yield point can't be shown by running a nut up and down the threads as the threads are outside the loaded area of the bolt. A conrod doesn't have threads beyond the cap. Only the threads very close to the termination point might show something. A better test is to just compare the lengths of the bolts.

[@PiratePawly]

Great video, John. I learnt a bit more regarding high tensile information. I have been using Bolt & Nut Australia for ages now. When I found them, not only did they have exactly what I needed it was also cheaper than the rest.

[@richardlove4287]

Top job again mate. Thanks for your time.

[@robi4387]

Thanks for a very clear explanation of tensile strength, yield strength, proof strength and design strength.

[@chapposa]

Thoroughly enjoyed this John. Thank you

[@Mr_Frazza]

Wow, this was really great to watch, i know a lot of this stuff as a basic given principal gathered and passed down from who knows where but to actually see the numbers with real and true understanding was a truly valuable insight. Aslo, i've found the same with Nut and Bolt Australia, they always have what you want.

[@tsr7198]

Excellent, clear tutorial. I really appreciated this video. Cheers from Kansas, USA! Subbed

[@RenoLaringo]

Thank you so much ! I've learned a lot of stuff here. Really enjoyed the torough explanation.

[@Lihaschu]

i dont remember the last time ive left a comment on a yt video. but this is too good not to praise. i'm not even into cars. but this was so well presented, so comprehensible, so fascinating it brought a tear to my eye. you're a fantastic teacher.

[@awakenotwoke1973]

Oh boy, oh boy. Who else can't wait for the response to the responses in a few days? One of the few occasions where the sequel is always better than the original.

[@AutoExpertJC]

It is, in a sense, a fishing expedition.

[@vincentrobinet2713]

Very interesting information. Even though I have been using a torque wrench for sky car maintenance I had no idea of the design tolerances involved. Thanks John.

[@squareyes1981]

I am sitting 2 metres away from a souvenir I recovered from the West Cork rally; a half a wheel stud with the nut still attached which I found in a ditch. Thank you for this. There was certainly a lot of useful information in this. I enjoyed finding out about degrees of angle.

[@cme2cau]

Some manufacturers (cough Mini cough) use self threading trilobe bolts on the suspensin. These are almost guaranteed to strip the thread in the aluminium component if reused.

[@shortlytall7926]

Thanks for the wisdom! Got a project on at the moment that will benefit from it, so perfect time even!

[@larry_dickman]

Not my normal field of work, but you kept me interested for 32 minutes. Thanks John!

[@AutoExpertJC]

Thanks for watching.

[@johnmollet2637]

Good information. I'm also still awake, it's only 02:14 here in Arizona. I'm a fairly recent subscriber and am really enjoying your channel, keep up the good work

[@AutoExpertJC]

Thank you very much. Love Arizona BTW. Only visited once, but very similar to here in many ways.

[@nickl2548]

You took the words right out of my mouth. Bring the breaker bar along !

[@confuzsays7196]

I love it when you talk about the "other" nuts and not your typical audience.

[@jakartausm5241]

I remember watching a doc about the making of the Forth railway bridge (Sydney Harbour is similar) and how the rivets were heated then hammered down and allowed to cool. And they stated that it wasn’t the rivets that held the bridge up - it was the friction. The cooling and shrinking of the river provided the friction between the members. Mind blown at the time but that’s what does the work - friction not the bolt. The bolt provides the friction but the friction still does the work. Once you get that everything else fall into place. Tighten the bolt to provide enough friction to do the job. (Head bolts not quite the same). A wheel nut provides the friction between wheel and brake disc and brake disc and hub flange. Torque spec is just a way of gauging that enough friction is developed to transfer loads to the correct/designed transfer/load points. I’m an unqualified autodidact. Get first principles right and everything follows from that.

[@lesmansom7817]

Nice one John. I did my apprenticeship on farm machinery and diesel equipment. The number of times I’ve had to gas axe bolts off farming equipment maintained by farmers that think there is no such thing as too tight is ridiculous. When you see a cheater pipe with flared ends on the cockies ute you just know it’s going to be tight.😎

[@sammyjones3500]

Truckies save their stripped overtightened nuts too. To compare them with the other truckers overtightened nuts. Seen it myself, I told him to take his bag of nuts and get out of my workshop.

[@timothyjamieson1282]

Educating my young fellah through watching your videos and doing. I literally rotated my wheels on my 05 Nissan Note today. 4x 12 x 1.25 wheel studs each wheel- him seeing the capacity of each stud from your chart- on this 1100 kg car shows him, they aint coming off by themselves! Thanks John, brilliant as always.

[@1967_RS-SS]

I'd forgotten some of that (and some was new). Thanks for the refresher. Nicely done video.

[@aussietaipan8700]

Truly awake and great video. I have 3 torque wrenches, 1/4, 3/8 and 1/2 inch. The smaller ones are used for smaller fasteners and alloy fasteners.

[@bobtaschler4561]

Way over my head technically, but it is nice to know that there are knowledgeable engineers out there designing stuff that accommodates my ignorance and keeps me safe.

[@robc5955]

As an amateur mechanic of some 30 yrs your explanation was perfect and shed light on my ignorance, thanks.

[@fookmyoldboots7208]

Great video John. Thanks for educating me.

[@akdenyer]

Thanks John, very good, no I did not fall asleep I love this stuff. did it all at university.

[@stevebosun7410]

Hi John, excellent and well put across. Thank you.

[@davidbrayshaw3529]

Excellent presentation. I learned a lot.

[@matthewblack5656]

I've rewatched a few of your bolt videos now. I love it, good work. Off to rescue training in 5, I'll have to watch this later.

[@AutoExpertJC]

No wukkas, Matt.

[@ChristopherHallett]

@@AutoExpertJC It's about time you made a mistake! I believe the correct spelling is "no wuckers", with it being shortened from "no wucking forries", itself derived from "no fucking worries". Although now you're probably going to explain how I got it wrong...

[@AutoExpertJC]

I stand corrected - please accept my unreserved apology for this transgression.

[@SafeTrucking]

@@ChristopherHallett Expertly and patiently explained. Slipshod linguistic misadventures cannot be tolerated!

[@duckingtonedits2369]

Great video. Thank you for making it.

[@desperadolighfoot8534]

I appreciate this video, great educative content. Tks🇨🇦

[@timothymusson5040]

What a great video! Learned so much!

[@robpinter5431]

Hi John, after 40 years in the automotive industry including Defence, quite interesting that the video topic started with wheel studs, with our vehicles we use the manufactures supplied wheel brace and sockets, an example is the G1700 Unimog, it came with a wheel socket and a 1 meter long bar, ( the specification of 400Nm with a 70 kg down force), so how does the average Army driver tighten the wheel nuts basically be pulling on the bar. Never seen them use a torque wrench. In the civi world, tyre shops use air tools and ugga dugs with colour coded extension bars, that have a rating on them to apply a certain torque to the wheel nut depending on their length. The automotive industry is far removed from the aerospace industry when it comes to applied torque to fasteners.

[@trueblue862]

After a 10hr day at work, I damn near did fall asleep watching this, but good information and well put together. If only I could get the apprentices to watch and understand it.

[@ktwn6702]

i'm 3 +/- 10% into this video and you got a follow cause your gave suck good info right out the gate when it comes to torque/torque wrench info~! JFC!!! this is so much good advise! ASC certified tech here. and you're the first youtube "person" to really talk sense i've watched!!!

[@fabshop6359]

Brilliant! Great stuff, John!

[@dandydenni1615]

Texan here and love your humor and content!

[@itaintrocketscience]

I’m a diy mechanic I clicked here to learn what I don’t know. Seriously!

[@jla3772]

Excellent video; very informative; watched it all.

[@fredsasse9973]

Great information in this video, thanks! When making up flanges with studs to pressure vessels on oil refineries the "bolt tensioning" method is used. This may be partially due to the amount of clamping force needed at these connections (the flange studs are in the 1.5 to 3 inch diameter range) which makes using a torque wrench impractical. However I think it may also be due to the higher level of accuracy the tensioning method achieves verses torquing. I couldn't help but notice a little peculiar measuring system reference you made that many of my Canadian acquaintances make: ". . . a 600 mm long breaker bar with a 1/2 inch drive".

[@brw3079]

As a retired aircraft maintenance technician, I salute your authoritative but common sense approach. Very thorough explanation of commonly misunderstood concepts. Well done.

[@paulputnam2305]

What a fantastically wonderfully video filled with awesomeness Extreme. Thank You for sharing your brain with us.

[@syntaxerorr]

Really great video! Thanks!

[@user-en9zo2ol4z]

I must say John, unless you seriously edited the first question, it was certainly the type of informed inquiry I would be happy to accept on a permanent basis. Most questions are naturally based upon total ignorance, and here you have a bloke asking exactly the correct ones that would apply. Lucky you mate.

[@arthurmoore9488]

This was very informative. Thank you.

[@jonathanstace7540]

On the topic of tyre shops not breaking studs. Does cross threading the nut onto the stud with an air impact count as breaking it?

[@SLOCLMBR]

Well, no; but it does count as being liable for the replacement of nut and stud.. or hub and bolt on vw or BMW

[@Bloodbain88]

Cross thread the nut and them smash up what's left of the exposed threads. That's what you call "farmer loctite".

[@guylaraway6102]

I worked with a guy, who claimed he was a mechanic, his go to when tightening one time only nuts was "a crossthread is as good as loktite". He was an absolute hack.

[@benalfano4533]

Um, yes, absolutely. Try it with locking lugs though if u really want ur heart broken, lol

[@jamesk7446]

Yup. Stud is ruined.

[@o4pureh2o]

Thanks John. Great information.

[@dscott1524]

Interesting talk. Another very interesting thing regarding threaded fasteners is the thread load distribution along the threads. It is not uniform as one might naively assume and you would be the perfect person to bring clarity to that. A suggestion for a follow up video. Cheers

[@stansbruv3169]

I just went back to school! Thank you for the education.

[@PaulBKal]

Brilliant info. Thanks so much

[@lumotroph]

Damn subscribed. Thanks for the actual clear info!🎉

[@nigelcox1451]

Great presentation, as usual. A few thoughts. Most automotive fasteners, for general use, seem to be 8.8, with 10.9 used for most suspension and steering applications, with the occasional use of 12.9. Need to be careful when replacing the higher graded stuff, as many people will just stick a suitable size bolt in. In the UK, often fasteners available at DIY and hardware outlets will be inferior grade, 5.8. Fine for assembling a fence, or furniture, but not good holding your wheels on. From a UK fastener specialist website, it seems teh highest grade stainless (80) is close equivalent to 8.8, so not good for the critical applications on a car that use 10.9 or greater.

[@xcofcd]

5.8? I never saw that grade anywhere here in Germany.

[@hotrodpaully1]

Wow here in the States you can walk into any hardware store and they will have any grade bolt you need. Both metric or SAE. Only exception would be if it was a really odd ball thread pitch or head design

[@nigelcox1451]

@@xcofcd Often lower grades below 8.8 have no markings on the head, so hiding their lack of strength. Flat-pack furniture uses lower grade stuff, as the loads are not great. Overtightening them tends to damage the piece being clamped, long before any fastener issues. Some will have marked heads, others not.

[@melgross]

@@hotrodpaully1really? I’m 74 and here in the USA most hardware stores don’t have most grades. I’ve been buying for decades. They do have unmarked “hardware store” grade (about a grade 2), and sometimes a few grade 5, but grade 8 and higher? Very rarely. Stainless, more and more. That’s generally about a grade 3. Metric? Well, now this depends on where you are and all of this depends on the size of the store. I buy most of my fasteners from McMastercarr. They do have most of what’s available and you can usually buy one, for,larger sizes, or five, or ten. All depending on the type and size.

[@ianmac2963]

Once again ... EXCELLENT ... Thank you JC

[@marksingleton7199]

Excellent. Very well put across.

[@PeterB12345]

Agreed, consistency is a great idea especially when installing things that spin round and round all day!

[@funkyfreshanalog3043]

Thanks for your work :3

[@superjimnz]

One big issue is aluminium fasteners which are often torqued to yield, and are supposed to be replaced EVERY time they are removed. Many people don't replace them however. Same goes for crush washers, they hold when you reuse them, but they have already been crushed the first time.

[@Protronics-au]

That explanation is awesome! Anything less in your repetition of the details would have been inadequate for my peace of mind. After having been a regular DIY mechanic for the last 50 years (taught by my father-engineer), I have been agonising over the reuse of suspension bolts and how I torque them, on my 25yr old Volvo. This Volvo's bolt sizes seem a bit over-kill in size to me (compared with VW), which allowed me a buffer as to when to replace them. Your comprehensive explanation was just what I needed to confirm that my decisions on which bolts that I replaced and how to torque them according to Volvo's specifications was correct.