How do trains go around bends? | Live Experiments (Ep 36) | Head Squeeze

[@wsc31]

An amazingly simple and elegant solution to a complex problem. Gives one a greater respect for the inventive genius of past generations.

[@YouRedix]

I was hoping for more of a "rails with an angle at the bend to prevent the train from tipping over" kind of video about trains going around bends. Instead, I watched this and learned some entirely new things that I had no idea existed. Totally worth it.

[@TheJaredtheJaredlong]

I so do wish trains were more commonplace these days. Everything about them is so cool

[@user-wk8vo4ju7o]

Woah, really in first time in my life I loved studying a concept 😭😭 thanks 🙏🙏

[@solesearched]

I never realized the amazing engineering that went into trains. Genius!

[@HenkJanBakker]

I actually figured that out in high-school. Because of that experiment where two cones connected at the base seem to role 'uphill'.

[@Taino21]

I love this channel. And that was a great presentation. All the presenters on HeadSqueeze should get awards. Thank you guys again. Awesome! !!!!!

[@Jayremy89]

I learned this concept along time ago but still great to see it explained again for some reason...

[@thanksfernuthin]

Do we know who the genius was that figured it out? It really is impressive.

[@darkshad109]

Duct tape is called duct tape here too. Gaffer tape is a slightly different. It has a different adhesive which allows it to be removed cleanly, so it's used when you want the surface to be clean after.

[@EzraMable]

I just looked this up. Gaffer tape is more like a specialized kind of duct tape designed to be able to be removed without leaving that sticky residue behind that duct tape typically leaves.

[@Crystothetal]

These wheels also help the train from bouncing all around and giving a bumpy ride and increasing the chance they just flat out bounce them into derailment. I love trains though, and since I'm American there's no shortage of museums and landmarks for me to get a fix. There's old gravity trains not far from me that carried coal down the mountains back in the good ol days, neat stuff!

[@StevoE26]

ok so that explains that, so how does a 30 ft straight and rigid box with fixed axles go around a corner without either the back or from end coming off seems to me like trying to put a square shape into a circle hole

[@stikibunn]

The angle of the curve and the length of the engine are carefully calculated so as to remain on the track. There are cases of some trains with unfangled driving wheels to cope with steeper curves. These will be kept on the track by the "pony wheels" or "leading wheels" but generally locomotives re designed with the angle of the curves they will encounter calculated within their design.

[@R9000]

A fixed axle was originally necessary as the drive from the engine would need to be transferred to wheels on both sides, which requires the axle to be connected to both wheels as the pistons which move the rods which turn the wheels move at the same speed. This problem has since been solved in cars by the differential drive, another piece of engineering genius.

[@SantaFebuff]

That would be the radius of the curve. It actually varies because some locomotives and cars have three sets of axles per truck/bogey, and some don't. The ones with less axles can round sharper radius than others. Basically, when you build a railroad, the government has guidelines and locomotive builder guidelines to follow. Some curves get identical, like if you're on a high-speed rail line, most curves will be broad, but some will be sharper than others, depending on the route.

[@Daren_PNW]

What about the more wheels a bogie has, or even the long set train wheels of steam loco's? This boggles me! The length of the long wheel set seems to overlap its length on a curve..

[@CaptinFonz]

its a variation of duct or duck tape but can be removed more 'cleanly' without leaving residue on what it was stuck to - named Gaffer as its used a lot by 'gaffers'

[@sammysalter]

The best video from live experiments yet.

[@Barachat]

Agreed. And you seriously don't need to beg for subscribers if you continue making quality content like you usually do. They will come by themselves and not be put off by "in-video" requests. I don't mind it when it's at the end of the vid though.

[@ThinJizzy]

gaffer tape is like duct tape, but it leaves no residue. It gets it's name because it is used by workers in the theater or film industry to label things or attach stuff to the set. The workers are called gaffers.

[@anthonynault]

I will be taking the train next week and now this is the only thing I will be thinking about!

[@nintendoatarikiller]

Also cars do not have truncated wheels like trains and to go around bends/corners it uses a differential so each wheel can spin freely (the outside wheel can turn faster than the inside).

[@ericlin4971]

Best live experiment

[@Voidlikestars]

Although those wheels didn't solve the problem with trains going around corners at higher speeds. Trains actually started out as all one price but then people noticed that this made them fall over when going around corners . So to fix that they seperated the first set of wheels on the train which is why the front swings out allowing it to go faster around corners

[@vanmaren962]

I've always wondered how this worked, thanks!

[@MikeDragon]

Basically the same here. What reminds me that it's best not is the fact that James May also is in this channel. I actually don't mind it when he asks to subscribe halfway a video. I guess hes just that entertaining.

[@MisterRandom101]

This was an amazingly informational video

[@junglespinner]

Train locomotives and hardware have always used a fixed-axle approach. A differential is only helpful when each wheel can move independently.

[@FolkRiot]

Does that mean there is a strict calculation that governs the angle of a turn? Of course there are limits and a curve cannot be to sharp. But based on the wheel design, are all curves pretty much identical? If not, to what degree can the curves differ?

[@darkshad109]

Sellotape usually refers to clear household tape you'd use for balloon hanging and such.

[@NoMoreLles]

thats why it has the string grid on it, it reduces the area of glue that can be left behind

[@onlynexus]

Solid axles are much more robust than any kind of open wheel or differential system. And differential systems are only on driven axles. The way the wheels are shaped also leans the train into the corner a bit.

[@Shezmen88]

Wolverine doing science, amazing. ;) and also, clever experiment and well explained! ;)

[@MacBeckett]

Good piece, and well explained!

[@thejackal007]

Brilliant explanation.

[@Saitothesushi]

This system works fine and you got to consider costs of fitting them and compare it with a slanted wheel design.

[@jostrander71]

Funny metal on metal contact with the flange makes the noise. Isn't the wheel and track metal on metal? Great video

[@torosyan]

i remember watching this experiment on how 2, took me back

[@AnniePrettyFace]

Wow, thanks! That was actually really interesting!

When I was a child my father explained it, but I did not understand it exactly. Thank you!

[@WizardChip]

This is something I've always wondered!

[@GundamZeroSeven]

I learned something new today. thanks

[@SantaFebuff]

Not necessarily. That's implemented to reduce flange and rail wear to make it less expensive to have curves... and that's only on select equipment.

[@pathologicaldoubt]

Very informative, great video

[@RenatoGrigoli]

Well... that was amazing!

[@alexhydron]

that was awesome, never thought about it

[@melissaquijano5726]

He should have said for the first 2 experiments: "Aw, crap. See, all those people on the train just died. We'll need to find a better solution."

[@Leopr1]

This was very cool!

[@kght222]

that flange isn't on the outside, it is on the inside. even your experiment proved that to be the best. how the hell did you not fix that in post?

[@RihadElite]

Subscribed a never regretted

[@SnowRaptor]

First because of the amount of torque involved, I'm not sure how reliable differentials would be Second because you want some sort of 'active' tangential velocity difference so the train can actually make the turn. If all wheels were free, thr train wouldn't turn unless it had a steering system like a car's.

[@yorrickwi]

all good and well but i ask you why didn't they just fit a differential?

[@CrazyBear65]

Streetcars used to squeal like that around bends when I was a kid. _"Errr-errr-errr-errr..."_ around a tight corner, _"Eeeeeee..."_ around a more gradual curve. Then they ripped up all the tracks from the streets.

[@NikkElektrik]

The British accent on its own makes this channel 93,2% more educational...

[@donyfreaky]

Dear HeadsqueezeTV people, please please please stop begging for subscribers. That is so pathetic for a good channel like this. As far as i'am concerned, people will recognize the high quality content and are smart enough to subscribe if they want more.

[@DrMo65]

Great, a demonstration of how a train wheel is tapered and can take corners and a cameraman who films from a useless angle to show the effect.

[@holnrew]

Nicely done, except for the misspelling of axle. Also bogies help.

[@February54]

What is the name of the background music 0:55-1:05 and 2:30-4:57. And where did you source it from? Thanks!

[@hamjazz]

You forgot to mention that the rails are canted inwarda at the top -usually at a gradient of 1/20 or thereabouts. This tends to centre the wheels so that on straight track you theoretically do not need flanges --but obviiously only on strsight track.

[@ALegitimateYoutuber]

i want to see a video on the stirling engine, because I kinda understand it but i'm a visual learner

[@SantaFebuff]

Indirect measurement my friend, through many many experiments and many many trials. Of course, that's the biggest problem with being a scientist (especially in quantum physics) is that you have to do experiments while holding on that you could disprove something seemingly concrete. Just have a look at the Rutherford experiment with atoms. Completely unexpected. =) Science is fun. You may find it interesting if you have these questions.

[@dwyt]

Great video man loves it :)

Well explained. RESPECT p.s. I'm pretty sure a lot of viewers here also watch Top gear lol

[@jordanmatthew4899]

How do steam trains have different whistles?

[@IJustLoveStories]

Just beware that the cheaper kinds usually ignore this completely and leave as much residue behind as possible. They are only gaffer tape aesthetically.

[@arcadyt]

Really good one! :)

[@ceejaybizzle]

I got that too. Thought I woulda been alone on that one. Strange.

[@houstonceng]

This explanation is often given but is not totally correct. The taper on train wheels stops the wheel set hunting That is, not slamming from one flange to the other. The taper is insufficient to act as a differential as described except on nearly straight bends. Basically, one wheel will always slip, and to stop the flange riding up the rail on tight corners, a guard rail keeps the opposite flange constrained . Hence the squealing on tight bends

[@oracuda]

So the flange normally touches the track and especially on bends?

[@TheKaeleron]

Highspeed trains also use superelevated or Canted track on curves.

[@PhyrIsSoCold]

Cool video. Very interesting! And in regards to the subscribe "spam," guys, it was only a couple of seconds. It's not a big deal.

[@darkshad109]

Trains have been going a lot longer than that, how were they handling bends back then if this model only came in the 50's?

[@Cooper19940323]

That way trains could take sharper turns, or at least I think they could :D

[@adeel256]

this was completely unexpected. mind = blown

[@BrandonHartmanGuitar]

I have seriously always wondered how trains did it. Now i know.

[@omeraskin79]

Good shit!

[@cghost4yt]

What is the chaos theory?

[@soundslave]

You are from the future my friend. The real deal is to have a maglev train in a vacuum tunnel though. No friction. Unlimited speed. Although a bit dangerous if a passenger opened the window lol.

[@UrbanPanic]

Fixed axles are much lower maintenance and are better at supporting heavy loads.

[@epicminecrafter1254]

Why dont use a differential?

[@jesssinkula4941]

what is gaffer tape?

[@Runix1]

I went down to read the comments when he talked about subing xD

[@TaufikAkbar7]

what about the japanese bullet trains that use flatter wheel? it's said that cone wheel will oscillate at high speed

[@brettknoss486]

If it's an undriven wheel you just have it on a hub so the axle doesn't turn, if it's driven you have a differential or a seperate motor. What he described is really unimportant since fixed axles with bearing replaced turning axles with bushings in the 1950s

[@Kayen4]

Headsqueeze is pretty much ran by BBC Worldwide, they have to make sure they use efficient call to actions so that they can earn back what they pay for it... Or something like that... I might be completely lost.

[@drpekn616]

Japanese engineers came up with this concept while building the bullet train in the 50's

[@xAsadK]

Wouldn't have know that if it weren't for you. Thanks :)

[@DemolitionTurtle]

Woah, that's awesome! ;D

[@bettigyv]

Check Richard Feynman talk about this, an how it was a hazing for freshmen in MIT university in department of physics!

[@you9783]

nope its used alot by people who set up stages to cover wireing and not leave residue

[@fireball79058350]

To be honest I thought they had independent wheels and bogeys. Thank you!!

[@thany3]

Why do trains not have a differential then? Wouldn't that make for easier engineering of the wheels? Or better yet, why is there an axle in the first place??

[@monkerud2108]

the problem is getting the angle right, if its too high it will turn slightly to much and then the other way and back until it derails.. :P this is why higher speed trains have more flat wheels... :P(means it cant corner as much ofc.... :P)

[@DinosaurBytes]

I've only just realised you guys use the red dead font!

[@b145701s]

Would a train be able to take corners if it used a diff? Gotta say, I really do "respect" train wheels :)

[@blackbombchu]

So the train goes towards the outer edge of the curve from centrifugal force and that makes a larger part of the wheel on the outer edge be in contact with the rail than the wheel on the same axle on the other rail.

[@SriTejaChilakapati]

blackbombchu Exactly..

[@ADailydoseofRandom]

Love thse and wld live to try em myself but theres alwaslys on thing i dont have

[@Talon3000]

And he didn't even beg for subscriptions!

[@Diell95]

that is awesome!

[@MatiProbably]

probably too complicated fro the 1800s and this system works just fine.

[@TheKaneDestroyer]

Remind me never to catch a train on the way to work.