Which Are Stronger Inch or Metric Bolt Threads? Hydraulic Press Test!
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- เผยแพร่เมื่อ 27 ส.ค. 2024
- How strong are hex nuts, bolts and bolt threads in inch and metric sizes? Are machined billet bolts stronger than store ones? We are going to use our 150 ton hydraulic press and 240 force sensor to find out!
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Do not try this at home!! or at any where else!!
Music Thor's Hammer-Ethan Meixell
"Everything went to shit" sounds about right for 2022.
Yep! Describes my stock portfolio last Tuesday.
"and here we go"?
Hahaha! Reminds me of a joke i heard once that involved a camel, a bucket of water and some tail pumping. I digress.
Sounds like life In canada under the liberals
You don't say.
He has the hardest nuts on TH-cam, so it'll be alright.
That’s the absolute best “expert opinion” I’ve ever heard! “Everything went to sh*t”! Really enjoy this channel!!!
It sounds even better in his accent too.
Who said Europeans don't have a sense of humour 😂
You can make a statement like this when you have the 'hardest nuts on TH-cam'
It's just "entropy"
"Don't be worried if your nuts are round."
Thank you! I was worried!
What would the results have been if they were a lil oblong? I must quit sitting on mine.
I would be more worried if my nuts started to smoke.
Mine are egg shaped...should I see a doctor about it?
@@alphaomega8373 I think that's already too late, sorry mate! Feel ya! :'(
@@opimus Mine smoke all the time. I've tried to get them to quit but no luck so far.
Would be interesting to see the various grades of fasteners to see if they live up to their rating. Grade 2 vs Grade 5 vs Grade 8
Beat me to it! I was thinking the same thing. As a retired Mechanical Engineer that spent most of my career in Forensic Failure Analysis, I find these videos quite interesting, as all of the failures I investigated I saw the result but never watched as it happened! 😁
@@PhilG999 Crazy story. I was in the consumer satellite industry as Director of Technology Services for Echosphere (later became Dish Network). The units we made contained a modular descramblers made by General Instruments to decode subscription services. GI was the only game in town so we had to use them. They also competed directly against us with a consumer line of their own. Let's say we were not friendly with each other. They reported to the FBI that we were compromising the decoders and that it was a threat to the security of encoded military communications. The GI decoders had nothing to do with Milcomm decoding but it did make an impression on the FBI and they raided around half of our locations. Big fun, guns pulled, phones pulled out of walls, file cabinets dumped out, then rounded up and stuck in a conference room for hours with no communications. Long story short, the FBI realized it was not true, had nothing to do with Milcomms security, we had nothing to do with compromising the descramblers. But was a very memorable event. 3 months later, I was in my office and looked out the window. Saw multiple black vehicles staging in a parking lot with lots of well dressed fit males with short hair cuts. It looked like it was going to be round 2 of raids. They loaded up took off and raided the business 2 buildings over. They were importing fake grade 5 and 8 fasteners on a very large scale. That was back in late '80s, I can only imagine what is going on now.
@@davep.7099 There's no telling. I worked for a textile company with a lot of mil contracts for hook & loop (velcro) and it was all made in China, but it got here and was cut to proper length, tested Q&A, etc. We also had zippers the same way. Because of the law being only 51% needs to be "made in USA" they got away with it for awhile, then YKK (a Japanese company) made a formal complaint with DoD and got the contract halted. Now compared to YKK you're talking maybe the company I worked for held 5% of the market and YKK held probably 30% of hook & loop and 98% of zipper. There's was made in Japan and assembled here to meet the 51% mark. It's all a damn shell game and a race to the bottom in my opinion. It's a damn shame too, because there used to be a time when quality meant more than quantity, but not any longer. Now it's all about who can make 500000% profit on a sneaker and be damned to hell the poor people that have to make this stuff for us. It's either live the life of a hermit in a small hut or be a member of society and exploit those people. Everytime I think I have it hard at work, I remember, "In China many of the plants have nets around the building to catch suicidal people, and those nets didn't stop the first 1k jumpers because they weren't there. China is now an imperial powerhouse steamrolling numerous 3rd world countries and instead of being a race to the bottom of quality; it's a race to see which nation can steamroll the most 3rd world countries. It's just a damn shame this is where we are 100k yrs into the species, right back where we were 12k years ago.
Indeed
@@davep.7099 I build very large machines, would be shook to know some of the fasteners were not graded properly, such as the ones used to keep the massive bearing of a crane boom attached.
"We have some nut smoke," is the best statement in the history of HPC.
Nut smoke, don't breathe this.
"We have the hardest nuts on TH-cam."
@@LuminalSpoon didn't try blending them yet
Nuts. Smoke `em if you got `em.
"Roasted nuts. Nobody likes roasted nuts." Should've used a tinfoil shield.
Lesson, if your nuts are too hard you might bend your shaft?
Could also mean that you have torsion or cancer but not guaranteed
Dont want to.bend your shaft that realy would hurt a lot
"You don't have to worry if your nuts are round" :D
And then everything turns to shit
Yes and you might get some nutsmoke, which sounds both painful and awkward.
I've "done the math" (a very long time ago) based on material strength and area of engagement, etc, and Metric and Inch are very close. As I recall, Metric fit standards come out slightly ahead of "inch", but the difference wan't much. But, that doesn't account for a lot of asia-made Inch bolts being made from "mystery metal" with the yield strength of soft cheese.
Here in the USA they're called chinesium.
@@byronlabelle7569 Or "Mongolloy"... Whatever you call it - strength of soft cheese...
@@byronlabelle7569 what about "bubble aluminum" which is nearly as light as ABS but breaks even easier... airluminum?
The test was a wash with the inch bolt being a grade 5 and the metric a grade 8.
@@scrappyitalian Metric bolt was a 8.8 which is same hardness as imp grade 5
Also good tip on making right sized threads on your DIY bolts is just look when it looks like it's ready :D If the starting diameter and tools are right then you get typically really close just by the looks also.
Yes
- since the cross section profile of the threads is triangular, it's easy to see right when they are done (stop when the flat area "on top" of the threads is all gone)
the difference between your bolt and the factory bolt, one: they are stamp forged and threaded using a device that acts like a vice and roller at the same time, also, the reason your bolt squished and didnt break, factory bolts are hardened and then tempered to a certain softness, different for each type, nice little demonstration there
@@jebowlin3879 you can buy machined bolts, as opposed to rolled bolts, and the machined bolts are typically the more expensive closer tolerance parts, and are always stronger, simply because there is very little material that is not used for load bearing in the area of the nut that is engaged.
Now Laurie needs to make a test jig, to test that the tensile forces on the bolt and nut are different than under compressive load. more approximates real life loading, put the bolt in tension and see what fails.
Will likely have to be smaller, with a M12 and half inch bolts for the test samples, simply because there will be parts flying off at speed.
Have you considered adding frequency convertor to your hydraulic pump? You could press last tons much easier if pump speed was like 1/10 of normal. In this video Inch bolt was pressed so quicly that it was anticlimatick after your own made bolt.
That's how my boss at my first job taught me how to cut threads
I really appreciate that this channel is still the same years after it started, and any time I have the hankering to see some wonton destruction and things getting crushed, it never disappoints. The hydraulic press android game is what brought me here, but the fantastic content is what kept me coming back.
Would have loved to see an infrared view of the homemade bolt/nut combo.
or spray paint half the bolts with the color changing paint....use two cameras to capture each side.
Quote of the day: "We have some nut smoke!" - 5:38
The way he says it hits just right.
Never heard those words before in any context
Nothing wrong with a bit of nut smoke.
@@sillypuppy5940 "Chestnuts roasting on an open fire, jack frost nipping at your nose..." The line of Jack Frost nipping at your nose replaced the original "Nut smoke going up your nose".
This is the most important news ever on the internet !!! 😎💪
Love the cross section content! For me actually seeing how things fail and the end result is just as interesting and entertaining as the crush itself :)
Thank you for the "freedom units" :)
2:34 I am so glad for that deep technical insight and explanation. I as a hobby bolt crusher wouldn't come to this conclusion
Glad you didnt call yourself a nut crusher…
The expert opinion was very scientific, " I'm going to say everything went to shit". Then, "I have the hardest nuts on TH-cam".....
Though about the same. Also "Nut smoke" 😂
@@Tenus123 "This guy blasts smoking nuts" might be misunderstood in some contexts.
"You don't have to be worried if your nuts are round." I am SOOOOO relieved!
"I have the hardest nuts on TH-cam! " We're all lesser men, Lauri.
😂😂😂😂😂😂
Only worry if you experience nut smoke ;)
Whether the threads are cut on a lathe or rolled through pressure makes a huge difference in strength! So we really need a more complete range for a fair comparison. Eagerly awaiting a rematch!
Rolled threads much superior. But rather than squashing, I'd like to see it stretched. Always found that the failure was at the end of the thread where it joined the bolt. They were aircraft quality bolts and nuts.
True! Rolled threads essentially forge the material, thus making it stronger.
@@dave20thmay I spent 8 years as Warranty Engineer for a Deisel Engine Manufacturer. One particular example of unintentional tensile strength testing immediately comes to mind: On this particular (BIG) engine the harmonic balancer was held to the crankshaft with a 50mm dia. fine thread bolt ~150mm length. Service dealer called me complaining that they couldn't break the bolt loose with 6 guys leaning on a long piece of pipe! They told me the bolt would turn a bit each time they leaned on it, but just wouldn't loosen. Hmmm. Got out my book for that particular engine and looked up the bolt specs. Asked the guy if he had HIS book out and he did. Asked if he noticed anything unusual in the spec. He didn't. Asked: "Do you see that 'L' after the thread size/?" Silence, then "SOB!" and he slammed the phone down. Yep they were trying to loosen a left hand bolt by turning it counterclockwise! Week or so later I got a package from them. Inside was the bolt. It was "Hour glassed" like a tensile test sample *almost* to the point of failure! Obviously "Not Warranty". That bolt spent years in my "desk artifact" collection! 🤣
@@PhilG999 I have never turned a bolt the wrong way,,,,,,,,. In the past couple of years, anyway. ,,,,
@@dave20thmay That failure mode at the end of the thread is as specified for bolts. If it breaks anywhere else, it is a fail.
Now that you've done fasteners, try pressing them through various surfaces, to see if the bolts will ever fail in practice (or if the metal they attach to breaks first!)
From practical experience - the bolts always break first if the material is similar to the bolt.
I have had to undo a number of pipe flanges by breaking bolts. As a note - do not use graphite on steel bolts as an an anti seize lubricant - graphite greatly accelerates corrosion on steel (copper, aluminium or molybdenum disulphide containing greases are much better).
@@allangibson2408 Interesting ! I have had nothing but good experience with graphite paste on water and steam stuff. Though mainly for stuff that gets taken apart yearly. Might be different after 25 years, lol. Im not trolling or anmything, serious question because i used to use the stuff on a weekly basis and never had much of an issue.
@@allangibson2408 there's a very good reason for that, graphite is slightly hygroscopic and mixes with water
that's why it is suggested for door locks since they are corrosion resistant and often exposed to the elements
not sure what the affinity of graphite does with carbon in steel in terms of corrosion
depending on the temperature, even grease can be good enough if regular maintenance is to be expected, but I have had very good experience with aluminium antisieze so far
really wish that more stainless steel was used, sure, it would be more expensive, but would make maintenance a lot easier
@@nathanwest2304 Look up the electrochemical voltage table for a carbon iron cell (that’s what you get when you add water).
Stainless steel will seize too under the right conditions (anaerobic usually)- molybdenum disulphide or silver plating is used to prevent this happening.
@@allangibson2408 thanks for the tip, now that you mention it, have a gander at aluminium-iron cells
There's a reason mechanics hate multi link suspension.
I wish you would have tested using the same material for all bolts & nuts. That would have been more accurate.
Without the yield strength and hardness of all the nuts and bolts being the same, this test is nonsense if you are trying to prove which thread type is the strongest. Also, the speed of the press ram needs to be consistent from test to test.
@@richardstadler1458 Yes, all bolts and nuts need to be made of the same grade of steel.
That was actually impossible because he does not have a clue what steel the manufacturers used. The only clue is that its a hardened steel but he obviously does not have a forge to harden his steel after machining it. From the video its pretty clear that if he would have hardened the bolt it would have performed more than twice as good as the cheap steel used by the manufacturers. Most machinists know that manufacturers like to cut costs by using lower quality steel because chances are the forces on the bolts will never exceed 30,000lbs. The material he machines with is probably really expensive and high quality so it would have been so much more stronger after hardening.
It doesn't really matter because the forces in this video aren't compareable to how bolts are used in real life.
in the video the bolt is under compression, in real life it would be under tension (and this really does matter)
Also, bolts are used not only for clamping, but also shear strength.
@@animefreak5757 At the threads, a 10 tone stress in compression affect the bolts the same way as a 10 tone stress in tension.
As seen from the threads, both are shear stress.
It's at the level of the rest of the bolts body that it makes a difference.
Lets keep ist that way: You have the strongest nuts on the internet. Yep!
Shopper to Hardware Store clerk: "Do you have metric nuts?"
Hardware Store clerk: "What do you think I am? A Robot?"
I worked at a car parts shop once and someone asked me with absolutely no preamble whether I had brass nuts. I told him no, it was just that it was a particularly cold morning.
@Forth Sadler BTW - brass nuts used to be used on exhaust manifolds because they never seized on the studs due to corrosion. Steel nuts are however cheaper (and simple bolts are cheaper still)…
I originally heard the joke when I was a kid, like over 50 years ago, that a man walks into a plumbing supply store and asks the salesman "Do you have brass nipples?" And the salesman's reply was the same as I mentioned above.
Ask the checkout lady if she has a cardboard box.
The bolt/nut grades need to be the same for everything, otherwise the test is flawed.
You mean fawked.
It is flawed fundamentally. Threads manufacture quality plays too big of a role here, imo; it does not matter nearly as much if they are metric or imperial, as the fundamental designs are the same. I only notice that for smaller threads, imperial ones look a lot coarser than metric ones.
@Victor Titov There are also multiple different imperial threads too.
UNC, Whitworth and BA are wildly different for example…
@@allangibson2408 Absolutely; the most common criticism of Imperial threads are that 'they' are 55 degrees pitch angle (apart from the idea of using fractions). UNF and UNC are 60 degrees the same as metric, Whitworth, BSF, BSP and some others are 55 degrees, and BA is 47.5 degrees. They all have their applications. Use the right tool for the job, and the right fasteners to hold it together.
@@andybelcher1767
One could argue that there is no such thing as an imperial bolt / nut anymore given that the official definition of the inch is now 24.5mm...
This is my favorite hydraulic press related channel. The commentary is wonderful
For those interested, commercially produced bolts are commonly made using sets of spinning rollers that are ridged and squash the metal into the shape of the thread. Some are still made using a die cutter (look up tap and die sets) or a screw cutting lathe but despite having a better quality thread they cost a lot more and take longer to produce than those with rolled threads so are usually only used when smaller tolerances and high precision are needed because of this
A comparison of UNC or UNF against BSW or BSF would be great. They're both inch thread forms, and for many sizes they have identical pitches, but the form factor of UN is 60 degrees (like metric) while BS is 55 degrees. The BS threads also have a radius which I'm told will reduce stress risers. Another great comparison would be metric (M) vs metric aerospace (MJ); the MJ threads also have a radius.
Could also do 30 degree TR (trapezoidal) vs Acme (29.5 degrees) for similar sizes too.
UNC/F and M have a radius too, on MJ the radius is larger than on M and it has finer tolerances
His 1'-14tpi would be UNS wouldn't it? I remember having to buy a die nut for a shaft with that thread when I was working in China. It was a prick to find but got die nuts and taps eventually.
@@ianmontgomery7534 yes, probably UNS.
Out of curiosity, what was the application?
The softer metal will always yield. No matter what, if the bolt OR the nut are hardened, whatever's hardened will cut right through the other without batting an eye
When both are hardened, you run the risk of it exploding, but otherwise it's like the difference between your lathe bit and the metal you're working. That hardened steel bolt likely didn't have even a single scratch.
Risk? More like opportunity
The engineers who designed fasteners knew about that, so they made the nut slightly less hard than the bolt. The nut almost exclusively always yields before the bolt does, unless there's an application for the bolt where a nut isn't used.
@@JosephArata We are over looking the nut grade and bolt grade. I didn't see any marking on the nuts so they were standard grade or grade 5. A grade 8 nut is way stronger and you can get 10 and 12. A grade 12 nut will not bend as much so will support the threads on the bolt better too. I would think most the bolt and nuts would go 35 to 40 ton with high grade nuts.
We use Grade 8 bolts on cranes in steel mills....We better get them off the machines before they explode and kill soebody. ,,,, Guess it;s better to have the crane collapse when the soft bolts pull in two. Appellation engineer at it's best.
@@mathewmolk2089 lmao
You sound like a tech illiterate boomer, I have a really hard time taking you seriously
Your flippant tone (with a completely different scenario) also doesn't help your case.
The results being so similar makes sense. Unified Standard Threads and ISO Metric Threads use the same 60 degree thread profile. They are basically the exact same bolts/nuts cut to a slightly different measurement system. If you made an M12.7 coarse metric bolt for instance, it'd function identically to a 1/2 inch UNC bolt.
The interesting takeaway is that both the metric and imperial bolts, which have a similar, not particularly high strength rating (metric grade 8.8 vs SAE grade 5), in both cases it was the nut that failed. We generally think about bolt grades, but often not nut grades, and perhaps we really should.
OMG the way the homemade bolt failed was fascinating! Your threads were stronger than the cross section of the bolt it seems! Also given they were the same material, I wonder if they essentially fused, seeing how the top of the bolt almost seemed to melt from deformation. Seriously cool! Actually slightly surprised by the metric fine thread winning, since SAE Grade 8 is supposed to be a fair bit stronger than Metric 8.8, but also not sure that was a Grade 8 bolt since it should be gold or black. That may not be universal though. Fun video.
"You don't have to be worried if your nuts are round". 4:53
...
However, if your WIFE tells you that HER nuts are also round, you can officially start being 'concerned'...
Would be neat to see buttress and acme thread type as well. Great video!
If we've learned nothing else from Road Runner cartoons re ACME - LOL.
The neat thing about bolts measured in Imperial units is, it's threads/inch. So, if you have a 5/16"x18, you have a 5/16" bolt with 18 threads per inch. Also, the fine-thread standard bolt is Grade 5, not sure what that equates to on the Metric side, but the coarse-thread bolt was harder than Grade 8. You can tell by the lines on the bolt head. Three lines are Grade 5, and they're either bare steel or galvanized, while Grade 8 has 6 lines and are typically electro-plated with Cadmium.
Man, i really truly fully (is this enough sarcasm?) Wish i used inch
@@angrydragonslayer It’s really not that hard...
@@angrydragonslayer you have WAY too much soy in your system to use USCS.
@@littlejackalo5326 i actively try to avoid both soy and high fructose corn syrup, tyvm
@@nocount7517 how much energy does it take to heat up your local variant of a pint of water by 1°f?
I cant remember the actual joke but i think this is good enough ¯\_(ツ)_/¯
Perhaps the nuts spread a little just prior to failure? The homemade one had more metal in the nut which could explain the results with it.
Most european available bolts are classified as "8.8" (800N/mm²) and the nuts that come with it according the ISO4014/4017 are a little weaker, so when something fails, the bolt most likely will keep things together. It's also clear to see that in most cases the threads are stripped from the nuts.
Nutspread?
I'd love to see a tensile strength test on the home made one
I’ve been away for a while. I’m sorry, but I’m back to enjoy your edutainment. Much respect.
There are also several fit specifications for each thread pitch, that define maximums and minimums for both the Internal and External threads. Also, note that your homemade threads are cut and the commercial off the shelf fasteners will almost exclusively have rolled/formed threads. Generally speaking the formed threads are much stronger, so my guess here is either you cut your threads to a tighter fit specification or the deformation of your demonstrably softer material means that the threads deformed into each other as it mushroomed on top, precluding the shear forces from acting on the threads like they did in the commercial fasteners.
I have always heard that you only need 3 coils of thread engagement to be at full strength. This would be interesting to test!
Around 90-95% of the full force is on the first 3 coils.
I thought it was one and half times the diameter
As long as 3 threads are equal to to 1.5xD your both correct
there are nuts with special geometry that spread the load equally, but they are more expensive and thus less common
1.5 x diameter
Cool video once again. The engine lathe takes me back to shop class in high school. The Stanley Cup I made as a class project for my dad is still in his room.
the way the smoke released from your nut & bolt looked pretty cool.
That's because his nuts weren't clean. He has oily nuts.
It is a relief to hear that theres no worry if the nuts are round.
Also, I hope that youtube gives you the hardest nut -award.
Would like to see acme thread test. Due to the threads being more square shaped than V shaped. Should hold up fairly well.
Bolts and fasteners are designed to be pulled and not compressed in most cases. Love to see you do a pull test on the same fasteners. Will the bolts yield and pull apart before pulling the threads from the nuts when using same hardness components?
@@falsteethmike every bolt stretches when it is tightened.
@@Alcogod OP is correct. It will not be the same because the failure mode is different. In compression the failure point is thread shear (stripped thread), as can clearly be seen in this video. In tension, the failure point is tensile fracture of the bolt shaft. Bolts are meant to be under tension, not compression.
This video shows the thread shear capacity, which is not relevant for high strength bolts IRL. A proper test must be a tensile test.
@@falsteethmike Your point is wrong then. M24 or any other size will break before it strips in tension. You can see tensile tests here on YT, or see images of the resulting broken specimen. That's exactly how the tests are done: a clamp pulls on the threaded nut and the bolt head. The thread stays intact. The shaft breaks. Always. The shaft is the weak point in high grade bolts, which is why the test in this video is irrelevant to real usage.
You are correct that the force required to strip the thread is the same in either direction, but the force required to break the bolt in tension is less than is required to strip the thread, so the failure mode is not the same.
@@falsteethmike The metric bolts in the video (not the home made) were both grade 8.8, which is a high strength grade, but the lowest among them (it goes as high as grade 12.9), so the threads will not strip before the shaft breaks in tension. Same for the fine SAE bolt which was a grade 5 - identical to metric 8.8 (I can't see the head of the coarse SAE bolt, so it might have been something else).
Low strength grades (less than 8.8 metric, or less than 5 SAE) might strip their thread when tensioning the bolt.
As for nuts, they're supposed to be of the same grade as the bolt, or one grade higher. I can't see the markings in the video so the nut's grade is unknown, however it looks like the thread sheared on the bolts and some of it became embedded in the mating nut thread.
@@falsteethmike Regarding your second comment, I'm not sure where you got these numbers, but they are incorrect. M24x2 mm grade 8.8 (the fine metric bolt in this video) has an ultimate tensile load of 319 kN, or 32.5 tonnes of force. The thread in this video failed at 35.7 tonnes, which makes perfect sense - the thread form is designed to be slightly stronger than the shaft.
If it was weaker than the shaft, the bolt couldn't be utilized to its full strength because the thread would strip first. If it was much stronger than the shaft, it comes at the expense of a weaker shaft (deeper cut thread).
M24x3 grade 8.8 (the coarse metric bolt in the vid) has an ultimate tensile load of 292.6 kN, or 29.8 tonnes. The thread failed at 32.9 tonnes, so it's the same story - the thread is deliberately designed to be slightly stronger than the shaft so the bolt can be tensioned all the way to failure and the full strength can thus be used in practice.
So I think the reason why the homemade nut and bolt squashed instead of broke is because the nuts and bolts you buy are made using cold-forging techniques. The cold-forging induces work hardening in the metal which makes them more likely to break than bend. The same/similar material in bar stock form is still (mostly) annealed and when it's cut/machined the material left hasn't undergone the same work-hardening methods. The cold-rolling still induces work hardening but you've cut that layer away in the machining.
It's so satisfying to see the thread being torn off
6:30
Freedom unit 😂😂😅🤣🤣🤣🤣
LoooooooL 😂
“I have the hardest nuts on TH-cam” 😂 Absolutely made my day that quote!
As a professional fastener manufacturer I just wanna point out that most production bolts are cold formed which is much stronger then cut which is how you make them at home. The process is both fascinating and results is significant strength increases. Also bolts are made to resist pulling forces rather then compressive which generally results in the head of the bolt pulling off well before any other part will fail.
But do you make round nuts?
The left bolt in the lineup is UNC (Unified Coarse Threads) the second one from the left is UNF (Unified Fine Threads).
From seeing how your bolt was malleable, I have a feeling bolt makers make the bolts and then harden them afterwards, as pre typical process with heat and oil. I'm not expert though, and this is just an assumption
Lack of fillet under the head might've played a role as well. Not crackin' on Lauri's ma-chining, it was about the threads.
It depends what grade of bolt is used. There are markings on the head that determine the tensile strength.
Bought bolts are normally a rolled thread, so the steel they use is manufactured to have less wear on the rolling dies, and then the bolt can be hardened later on. Shop nut showed that the nut manufacture is the important part, as the nut did not fail, and the closer tolerance between nut and bolt threads means higher resistance to tearing the threads off. Make the bolt to the same tolerance as the bought one and not machine for close tolerance fit and it likely would have stripped threads around the same point.
Would be a good thing to redo using not regular nuts and bolts, but instead using some precision nuts and bolts, with closer tolerance, and also using higher strength steel bolts and nuts as well as mild steel, plus stainless steel. With the steel all you are doing is showing that thread engagement, in the bolt and nut as assembled, is giving more force transmission than what the actual underlying steel can bear before failing, as all the failures were bolt thread shearing off. Nut is stronger simply because the shear forces were transmitted into the parent material, and the shop cut one showed that, with the outside bold undergoing plastic deformation before the thread failed.
More importantly, with the shop made bolt, did the nut unthread with ease, or did it gall shut on the top two turns of thread in the nut as well.
The hardness of regular bolts is achieved by rolling the threads on rather than cutting them. By working the material while cold, it hardens and gets stronger, but more brittle.
If you take some steel (that has the same strength as labled on the regular screw) and make a custom screw of the same size by cutting it, it is stronger than the regular screw. Thats because the material can also "work-harden" during bending and increase its strength even more. This effect only works once. So the regular screws start with a lower-strenght steel to begin with, and achieve their higher rating just by the rolling of the threads.
Also, the round nut had much more volume surrounding threads to handle much greater pressure. You could see the coarse thread freedom unit nut expand after about 5 tons while the machined round nut likely didn't expand at all or by a few microns at the top.
7:10 8 inches per thread is pretty large, yes, larger than the regular M24.
How have I not been here before? I hope this guy is now a millionaire due to TH-cam. He deserves it
You should try to press 3 metric bolts of the same size and material and 3 imperial bolts of the same size and material and compare them.
For example, three bolts of 25 mm and three bolts of 1 inch same material. Press it and compare them. (1 inch is slightly bigger than 25 mm.) Then try three more bolts of 26 mm (slightly bigger than an inch) and press them. Compare them. 👌
Hey Lauri - can you please make a video of you fabricating a homemade wrench, for your homemade bolts? I think that would be very interesting!
I think they would look like vise grips and they would probably only tighten to like 20 ft lbs
If you really want to know what the "real" force is it withstands: find the exact time when the thread deforms (!) (end of elastic deformation => beginning of plastic deformation) Way before it gives way!
This would be real number!
Cheers for the entertainment!
It's literally referred to as elastic and plastic deformation?
Elastic must be how much it can stretch and still go back to roughly where it started?
Then plastic must be the point at which it's been compromised and will never be the shape it started, possibly more importantly the material's been stretched to the point of being brittle and can no longer be said to have the rated strength it once had? Much like plastic when it's been, say bent in half? It'll never be straight again and a brisk wind could knock it over at the fold after being compromised in such a way?
These are all just guesses, as you can tell I have no idea haha.
@@derekspringer6448 That's exactly what it is.
@@derekspringer6448 Grab a used book on Strength of Materials. A very satisfying read if you are into this stuff.
He's obviously testing them to failure.
@@River_Miles Good recommendation, maybe I should. I do have a love for absorbing knowledge! Haha. Thanks for the suggestion buddy.
the inch bolt, the grey one with 3 lines on top of it is a grade 5 bolt. I would be interested in seeing a Grade 8 bolt which will have 6 lines on top of it, paird with a grade 8 nut. We seen that most of these that the threads in the nut went first so that makes me believe these nuts just wherent as strong as the bolts. good video
I agree. Compare a grade 8 bolt and nut to a 12.9. This may lead to explosive results.
"We have nut smoke " and " everything went to shit" welcome to 2022.
"I have the hardest nuts on the internet" best quote I've heard in a long time!🤣
Text on a T-shirt! 🤣
@@274727 Needs a picture of nuts
The dark bolts are graded steel, while the bright ones are low grade or non-graded steel. The bolts are all non-graded steel as they all have the same shiny colour. You should have bolts and nuts of matching grade for this test to be correct.
Not true. The silver bolts are zinc plated. The black ones are phosphate plated. You can have any grade of bolt plated in either. You can also see that both the silver and black metric bolts have the same grade 8.8 stamped on the bolt head, which is considered a high strength bolt (but the lowest among the high strength grades).
You can also see in the end that the silver SAE bolt has three lines stamped on it, which designate it as a grade 5 bolt, which is the same as metric 8.8, i.e. the lowest grade of high strength bolt.
Would like to see a comparison between cut and rolled threads.
The bolt and nut material is the most important thing to quantify in this whole experiment… its like trying to find out the animal with the fastest speed and you have a tortoise, giraffe, cheetah, and a grass hopper but animal species unknown
Lauri, what was the raw material grade for your shop-made nut & bolt?
Just a wild guess, but from the surface finish of the raw stock it looks to be some form of hot rolled steel
did your home made screw come out of the nut after?
I didn't actually try. I can try tomorrow and report did it open :D
I'm also wondering this, that would be a big success. Personally I think it had a lot to do with better tolerances and softer materials
It'd be interesting to see some more uncommon thread types like acme, British standard whitworth, etc.
An infra red camera might be a good addition to this setup to maximize the science value of these experiments.
4:52 Nothing wrong with a round shaped nut...
A round nut is hard to get a grip on.
Whether they are measured in inch or metric makes no difference. It is the material, diameter, pitch and thread depth. So convert all measures to one or the other and use that for comparison.
I think that’s very obvious so I think he’s making a joke lol.
It's amazing how much heat compression can create. This literally starting to smoke from that heat is so impressive.
This is very interesting and thank you for taking the time to carry out the experiment. I have read several of the comments below and they are absolutely correct in pointing out the different materials. There is another point to make - modern mass production methods only look for between 60% and 80% engagement in order to ensure that every nut fits every bolt, so the percentage engagement also plays a part. Being as you made one nut and the bolt to fit it I can imagine that you got about 95% engagement which makes for a massive rise in thread strength. I think that you are right, it is entertainment more than science.
Not sure what engagement means. I could probably guess it's slack. Also another factor might be angle. I think the standard is 60 (30 from perpendicular) degrees. That could be varied as well. The metric vs. imperial premise was silly to begin with. More so, one should have sorted by thread pitch - no matter what the underlying scale is. Thread depth also (related to angle). Also there are double threads, etc.
@@billr3053 Hi Bill, it means the amount of metal left to fill the space in its opposite V. 100% engagement means that there is no space left over...and would probably seize when you tried screwing them together. There has to be a certain amount of free space. On mass-produced nuts and bolts, particularly at the cheap end of the market, to ensure that every nut fits every bolt, the free space is greater and the engagement, the amount of metal on opposite faces actually in contact, is reduced. Think of the different fits for plugs in holes, press fit out to sliding fit...or even 'fits where it touches' like some of my disasters :-)
I mean whats going to determine the strength of a bolt are mainly how coarse your threads are and what material/grade the bolt is, not it's system of measurment lol
Fun video either way:)
If there is a way to poke fun at Americans, none of that matters.
not to mention this is probably the one force nuts and bolts don't experience in normal applications
@@johncoops6897 SO true lmao. I'm a toolmaker in Canada though and I get to work with BOTH at work so maybe I can't talk too much 🤣
@@ionymous6733 Plenty of bolts are under tension and compression, especially in manufacturing equipment using much stronger presses than this machine, although threaded holes in material are more used than through holes with nuts.
@@bobbymelehes732 - I'm in your sister country, Down Under in AU. We have a duty (just like you guys) to take the piss out of them at every opportunity.
I grew up with Imperial, then changed to Metric in my late teens. We still use both measurement systems.... actually, it's WORSE here because we have three...
Whitworth = British lunacy.
SAE/Unified = American madness.
Metric = everything modern.
I say that because I'm currently sorting out my dad's huge number of Taps and Dies, and we also have BSP, NPT (and tapered for both), as well as BA and some other strange Gas and Water ones I cannot remember right now.
I would like to see this done on a custom bolt/nut made using ACME thread. Wonder how that would do?
ACME Corp. does not sold taps and dies, sold anvils and explosives only, but it went bankrupt when the Road Runner died under unexplained circumstances.
Should be much stronger as ACME, square and buttress thread are power screw threads and are therefore meant to take compressive loads. Normal bolt threads, be it metric or SAE, are meant for tensile loads. A normal bolt never experiences compression, only tension, which is why this test, while entertaining, has very little real life relevance.
@@ASJC27 What about elevator bolts? The sorts of bolts used to level-off machinery or fixtures are not usually acme thread, and they're in-compression rathe than in-tension.
@@TWX1138 those have to deal with very low loads compared to the loads bolts are typically subject to when properly torqued, so the thread form doesn’t matter.
In this case it’s better to use a more common thread, that can also be mass produced in industrial thread rolling machines.
BTW UNC and metric threads are used sometimes for power screws, but only for low loads. For high loads, that’s what the three mentioned in the previous comment are for.
Acme are not made that way for for strength at all. They are made that way because they do not seize up after being over stressed like you do with C clamps or vises.
“We have some nut smoke.” LOL, can’t say I’ve ever heard that expression before.
The Finnish flair adds points and different perspective to all things in life. Including toying around with a press!
Yo bolts are meant to hold together under pull forces not pushing forces
That would only test the strength of the bolt, not the threads. Pulling them apart would make the bolt yield, not the threads. This is a test of the threads.
Reminds me of when I worked at an auto parts store, on a weekly basis I would have an old guy come in (rarely the same one twice, but always an old guy) with a bolt or two that was stripped and needed matched up. My usual first question towards finding the correct thread and pitch was if it was metric or SAE and more often than not I would then get yelled at " I don't want any of that metric junk!". I eventually stopped asking and just had my own process to get the right thing, seemed easier than upsetting someone who would be indignant over a GM product using that "that commie nonsense". I'll be so happy when the imperial system of measurement is just a page in the history books, kinda like whitworth.
Yes you'll be happy when the USA is on the scrap heap of history. I'll remind you of that when you're in the gulag too.
" hey, we have some nut smoke" not a phrase I was expecting to hear today. but I'm glad to have heard it
Testing fasteners could be one hell of a rabbit hole!
A pleasure to watch, however I am glad that scientific studies/tests are done in a proper controlled manner, in engineering “similar” quite often spells “disaster”.
"Nut smoke" my new favourite saying from your channel! Definitely the hardest nuts on TH-cam!
1 inch is 5,83% larger than 24mm, but I think the largest factor is the length of the thread in the nut. Especially the fine threads having a smaller chamfer in the nut, so a larger thread length for the same nut height.
It would be interesting to repeat that using Whitworth threaded bolts which have thread pitches and angles designed on the basis of mechanical strength rather than mathematical convenience like most of the other systems.
Really cool to see the strength differences, i do have a request as a follow up on this how strong is acne thread?
I bet it pops like a zit
I watch this channel regularly!
I do think part of this was material failures. The shiny bolts are most likely just your common zinc plated bolts and nuts where the darker ones are most likely grade 8 bolts which are harder and have lower tolerances. It would be interesting to see this test again with all bolts and nuts of the same material or even a compresence of the two different materials.
"You don’t have to worry if your nuts are round." Whew! I can’t tell you what a relief that is.
Try axialy pressing inner ring of ball bearing out. Try without radial restraining of outer ring and with radial restraining (make a housing that sits the outer ring). Push the inner ring with a shaft that has a ledge (bigger diameter) that inner ring rests on. All tolerances on the rings should be bit loose so you can get outer ring out of the tool and shaft out of the inner ring.
Very useful for when I build my Frankenstein monster. The critical bolt of course is the one through the neck.
"You don't have to be worry if your nuts are round"
"We have some nuts smoke"
The Hardest Nuts on TH-cam. Congrats!!🎉🍾🎈🎊
This really is the best channel on TH-cam. I used to do a lot of machining and I always wondered if there was a difference between rolled threads and cut threads? Perhaps that could be a future competition?
I am not sure how much difference it would make, but I would prefer a pulling force on the bolt. The threads should be optimized for pulling, so that all threads are in contact when the bolt gets longer from the pull force. I suspect that much fewer threads will be in contact when you make the bolt shorter by pushing it, so the force will not be evenly distributed.
Holy smokes! You should sell some of these smashed nut and bolt sets as merch!
If you think about it, thin thread has weaker threads, but more of them, so it should even up and if you calculate it mechanically, it actually does.
I've just started the video. As a British man who left school in the mid 90s I had the enjoyment of being taught a "are we or aren't we metric" system of an ungodly mix of imperial and metric measurements. MM, CM inch, foot, metre, yard, mile....like that. I have lived and worked in both mainland Europe (where I am permanently living now) and the USA and I can state categorically! Metric wins. Its so much a better more logical system. I couldn't tell you how big 7/32 of an inch is without dividing 25.4 by 32 qnd multiplying it by 7. Imperial is from a bygone era with only two countries on the globe using it!
Yours failed differently as the commercial bolts are induction hardened after being rolled.
If you look closely on the second one you can tell only the nut gave way. the bolt stayed intact
materials play a very important part in how durable bolts and nuts are depending on the load used a grade 8 is so hard they are brittle while a grade 5 can deform under load the grade 8 will snap as soon as a shearing force is applied sufficiently the grades can be determined on US bolts by the number of line marks on top
Thousandth/10 thousandth of inches we use in Aviation.
Coarser Threads are for Speed, Finer are for grip strength.
Would be cool to just see a whitworth vs unified thread, NC W vs UNC
The homemade bolt was not heat treated. Most commercial bolts are.
Very impressive work on the homemade bolt/nut! Also was kinda surprised to see the M24 bolt outdo the larger 1-inch bolt... maybe the Class 8.8 metal is stronger than the Grade 5?
It'd be interesting to see a showdown between Grade 8 and Class 10.9 hardware as well!
Hey! You should know that there is a minimal thread length required! Since your bolts are class 8.8 and assuming the steel Rm is > 600...800 N/mm2 you need a minimum of 1.2xD. Since your bolt is a M24 it would be 28.8mm of length. Use the same length for every bolt as well, otherwise the results wont be accurate! The bolt you made was probably not made from a carbon steel! When a bolt "breaks" it shouldnt be deformed like that.
So maybe do a make-over video! Would also be great to calculate how much a bold should be able to withstand and then test it!
Anyway, love your videos keep it up!
Nuts are 0.8xD thick with a useable thread length of 0.5 to 0.6xD