# Tool Talk >  Richard Feynman explains: What keeps a train on the track?

## Jon

Nobel prize-winning theoretical physicist Richard Feynman explains what keeps a train on the track.

2:26 video:





Previously:

Janney semi-automatic railway coupler - GIF and patent
railway construction machine GIF
wartime railway and train sabotage techniques
Making an anvil from a railroad rail GIF

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volodar (Oct 16, 2018)

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## rgsparber

One of the great minds of our time! I think he was stuck at being 10 years old for his entire life.

Rick

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Drew1966 (May 24, 2020)

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## mklotz

My ascender...

http://www.homemadetools.net/forum/rolling-uphill-51682

demonstrates the RR wheel effect vividly. The video doesn't show it because I put the double cone on the tracks nicely orthogonal. If the ascender is placed crookedly, the varying rolling speeds induced at the two ends of the ascender will quickly make it straighten out and roll parallel to the rails.

As a kid, I knew from "helping" my Dad with car repairs that the wheels had to turn at different speeds when turning. So, the first time I saw a box-car truck close-up I was puzzled. My Dad didn't know enough physics to explain it to me so I had to wait until my sophomore year in college when we studied rotating bodies for the penny to drop. 

Feynman guest lectured a few times while I was at Tech. He was an absolute delight. It was as if he was telling you a wonderful story and you couldn't wait until he revealed the next detail of the plot. It was the way physics should be taught.

Read any of his books. They are a revealing peek into the mind of a genius with a distinctive, impish, mischievous mind mixed with a no-nonsense approach to physics that could penetrate to the core of a problem in a twinkling.

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## rgsparber

Marv,

My favorite: "The Pleasure of Finding Things Out".

I did talk to a guy that was going for his Phd and did his orals with Feynman in the room. Apparently he didn't suffer fools well. By "fools" I mean people not as smart as he was. 

Rick

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## JohnMTO

Goin to San Francisco Going to play my bongos in the dirt!
Thanks Richard F and Thanks Frank Z

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## mklotz

> Marv,
> 
> My favorite: "The Pleasure of Finding Things Out".
> 
> I did talk to a guy that was going for his Phd and did his orals with Feynman in the room. Apparently he didn't suffer fools well. By "fools" I mean people not as smart as he was.



I think he recognized that few could be as intelligent as he was but he was indeed put off by people who did not use what intelligence they had to the full extent. A hint of this is something he said while summing up his work on the Challenger explosion...

For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.

Another of his favorite sayings in the classroom...

The first principle is that you must not fool yourself - and you are the easiest person to fool.

seems to hint at this idea as well.

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volodar (Oct 16, 2018)

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## Jon

Following a lecture, Feynman indulges in a conga drum rendition of "Orange Juice". I believe this was recorded somewhat shortly before his death from cancer in 1988.




Feynman was an amateur but _highly_ enthusiastic drummer. It is rumored that one of his wives left him in part because of his incessant bongo playing. His percussionist leanings, combined with his appreciation of the ladies, and of course the Nobel Prize bit, led to this excellent _What Would Richard Feynman Do?_ flowchart:

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## mklotz

I suppose one could say that, except for that intuitive comprehension of quantum electrodynamics, Einstein award and Nobel prize business, Richard never completely outgrew his adolescence. :-)

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## Frank S

I'm not so sure one really should completely out grow their adolescence. Many who were considered to posses extraordinarily high intellectual skills or inventive abilities . were looked upon with scorn by society at large because of certain characteristic traits they exhibited. Which were considered flaws by society in mass.
These so called flaws or unwillingness to conform to societal norm very possibly may be part of the trigger mechanism which allows their creative intuitiveness to flourish.

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Scotsman Hosie (Apr 1, 2018)

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## Jon

Why train wheels have conical geometry.



Your browser does not support the video tag.

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## Frank S

A good demonstration

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## j.bickley

Very illuminating! Thanks!
---Joe

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## Scotsman Hosie

Nice follow up to your previous post - where Feynman _explained_ the principle. Seeing is believing _understanding._

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volodar (Jun 5, 2019)

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## volodar

Does anyone know how the wheels are fixed to the axle? One of my neighbours uses a train car wheel as the bottom mushroom anchor for a mooring. He might know (metal shop teacher at our high school) but I'd rather ask the group - then surprise him.

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## Frank S

> Does anyone know how the wheels are fixed to the axle?  One of my neighbours uses a train car wheel as the bottom mushroom anchor for a mooring. He might know (metal shop teacher at our high school) but I'd rather ask the group - then surprise him.



Here you go What they don't explain is the wheel is quite a it warmer than the axle

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Jon (Apr 3, 2018),

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## Jon

Richard Feynman reveals what makes a man a great intellectual, and someone he can easily talk to and see as an equal. Has nothing to do with his specific field of study; Feynman even speaks well of a modern artist.

According to Feynman, it's all about pushing your field of study as hard as you can, as far as you can go, such that you are "up against mysteries, all the way around the edge". 2:22 video:

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## Frank S

He was absolutely correct I have no more in common with an advanced nuclear physicist than I do with a brain surgeon or a lawyer and a politician but we can all sit and carry on a quality conversation, well maybe not so much with lawyers and politicos since so many of them have very limited intellect thus have closed off their minds.

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## Jon

Feynman made from Feynman diagrams.



Your browser does not support the video tag.

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## ranald

good looking shady character.

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## PJs

Excellent...Love it's creativity!

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## Jon

Feynman notes available online, with viewer app so you can see the original written notes: Feynman's Notes for The Feynman Lectures on Physics . There is enough here for some Feynman wallpaper.

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## mklotz

Or you could use them to create your own version of the Feynman van...



Elementary physics diagrams would probably have better appeal to the motoring public than Feynman diagrams...

https://en.wikipedia.org/wiki/Feynman_diagram

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## Paul Alciatore

The same effect is also one of the reasons why traditional barrels are fatter in the middle and smaller at the top and bottom. In the days before every warehouse had a forklift or, at least, a pallet jack, barrels were moved around the warehouses and moved in and out of trucks and RR cars by setting them on wood rails on their sides. Then they could be rolled for great distances on those rails and they would stay on the rails due to the self steering effect that they share with RR wheels. You can see this at work in old films of barrels running on wood rails. They would wobble first to one side and then to the other, but they would always correct their course and stay on the rails. 

Something our grandfathers knew, but we have forgotten. Well, some of them, anyway.

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## mklotz

> The same effect is also one of the reasons why traditional barrels are fatter in the middle and smaller at the top and bottom. In the days before every warehouse had a forklift or, at least, a pallet jack, barrels were moved around the warehouses and moved in and out of trucks and RR cars by setting them on wood rails on their sides. Then they could be rolled for great distances on those rails and they would stay on the rails due to the self steering effect that they share with RR wheels. You can see this at work in old films of barrels running on wood rails. They would wobble first to one side and then to the other, but they would always correct their course and stay on the rails. 
> 
> Something our grandfathers knew, but we have forgotten. Well, some of them, anyway.



Ah, but, Paul, this beggars the question of

Did they know about this effect before they started building barrels or did they discover it after they had worked out a technique of building a liquid-tight wooden container from slats?

I don't know the answer but barrels are older than railroads so I doubt they got the idea that way.

An associated question that has always intrigued me...

The ancients quarried and transported over long distances huge, heavy blocks of stone for their mega-constructions. Archaeologists theorize they used sledges dragged on rollers for the most part*. However, it's known that the Romans (and probably others) built cylindrical wooden structures around stone slabs and rolled those, possibly on temporary tracks laid for the purpose.

Now steering these monstrously heavy cylinders would have been difficult at best. Is it possible that they accidentally discovered the self-steering properties of the barrel shape?

---
*Exceptions include "walking" the giant moai of Easter Island and the use of purpose built ice roads by the Chinese during the construction of the Forbidden City.

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## Frank S

> Ah, but, Paul, this beggars the question of
> 
> Did they know about this effect before they started building barrels or did they discover it after they had worked out a technique of building a liquid-tight wooden container from slats?
> 
> I don't know the answer but barrels are older than railroads so I doubt they got the idea that way.
> 
> An associated question that has always intrigued me...
> 
> The ancients quarried and transported over long distances huge, heavy blocks of stone for their mega-constructions. Archaeologists theorize they used sledges dragged on rollers for the most part*. However, it's known that the Romans (and probably others) built cylindrical wooden structures around stone slabs and rolled those, possibly on temporary tracks laid for the purpose.
> ...



Quite probably the discovery of rolling barrels on rails may have been the result of trying to figure out how not to drop a barrel off of a gangway while unloading them from a ship. 
Large pottery jars predates wooden barrels but they were difficult to transport when made very large. Wooden buckets may have predated barrels as well. handles could be installed in them and they could be carried in multiples on yolks like smaller pottery jars, but buckets are difficult to seal preventing spillage in the holds of ships also they are difficult to stack unless and empty bucket were placed upside down on the one below it then another row cold be stacked on top. the shape of 2 buckets stacked together and large pottery jars resemble that of a barrel hence the advent of a barrel now they had something they could fill seal and lay on its side and roll up a gangway. However off loading posed problems the fat bellied barrels were difficult to control while descending and would roll off the edge of the gangway so a barrier would be required. The barriers it soon may have been discovered could keep the barrel rolling in a straight line as long as the belly of the barrel did not touch the gangway. This may have been accidental when the barrels became larger making them longer than the gangway was wide. the advent of the railway and the subsequent shape of the train wheels may have been borrowed from the learned process of rolling barrels on the side barrier rails of the gangway

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## rgsparber

Marv,

Seeing multi-ton blocks of stone wobbling down the road sure would scare me!

Rick

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huskyowner12 (Oct 16, 2021)

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## mklotz

> Marv,
> 
> Seeing multi-ton blocks of stone wobbling down the road sure would scare me!
> 
> Rick



For the benefit of the folks who don't know what we're talking about...

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Andyt (May 24, 2020),

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## rgsparber

Brings new meaning to taking your pet rock out for a stroll!

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Scotsman Hosie (May 31, 2020)

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## Jon

Hunting oscillation




I like this 1941 patent for a corner turntable for rolling barrels on rails too:

Corner Turntable for Rolling Barrels on Rails by S. Jeromos - US Patent 2,230,038

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Scotsman Hosie (May 31, 2020)

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## Frank S

> For the benefit of the folks who don't know what we're talking about...



He has to wobble they have him blind folded with all of the ropes  :Thumbs Up:

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