History of Ball Bearings (1981) [pdf] | Hacker News Reader

History of Ball Bearings (1981) [pdf]

ntrs.nasa.gov

During my visit to Venice I found a museum with interactive exhibits by Leonardo da Vinci. It's actually hard to appreciate full scale of his genius unless you actually try out each of the devices he created by your own hand. Most of these devices are very minimal and simple, something even you could build in half a day with right tools, but just magical. Even more importantly, what I learned was that he didn't just pulled them out his brilliant brain in one stroke. He meticulously studied how extremely simple things like gears, pulleys, levers, wheels & axle, inclined planes, friction, and screws behave and why do they behave that way. Then he started studying how lot of medieval machines that were already in existence simply be viewed as composition of these simple elements. Then he studied newer ways to compose them to build ever more complicated machines. So after years of such studies he was able to create these magical devices which worked without electricity, steam and such way back in 1500s. One of the device on display was ball bearings he had made and he was generally attributed as his inventor.

I opened it looking for my favourite bearing, and it is indeed there.

Page 34, Section 1.7.1 The Bicycle Bearing

"The demand for large numbers of steel balls... provided the ideal commercial conditions"

When I get a puncture, I glue a patch onto the inner tube and pump up the tyre again. When the handlebars wobble, I tighten them with an Allen key. When the brakes fail, I can adjust the cables to tighten them or realign the pads. I can always keep the half-broken bicycle moving.

But when the rear bearing is broken, my bicycle simply won't move. Taking apart the wheel takes a lot of work. The fastest, cheapest way I've found is to replace the whole rear wheel with one from a scrapyard.

I think it's not an exaggeration to say that the rest of the bicycle is just an accessory to the ball bearings.

I've discovered, at various points in my cycling career, that rim splits, broken cranks, and broken chains also tend to severely limit the functionality of a bicycle. Though yes, the role of bearings (found in wheels, bottom brackets, and headsets, BTW) is surprisingly crucial.

You've experienced a lot! Thankfully I never had a rim split or a broken crank.

I had a broken chain on 自由路 (meaning Freedom Road), when listening to a song with the lyrics "every chain is broken".

I could still use it like a velocipede and scoot forward with my feet to the nearest metro station, though.

The back bearings probably break on me more often because my bag's heavy.

All the figures are at the back of the book, if you happen to start reading and were wondering where all the pictures they were referencing were.

TIL "Tribology": the study of friction, wear, lubrication, and the design of bearings; the science of interacting surfaces in relative motion.

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

Or as Coulomb said in 1785 "Theorie des Machines Simples, en ayant egard au frottement de leur parties, et a la roideur des cordages," See: http://gallica.bnf.fr/ark:/12148/bpt6k1095299

There are 22 pages of references, besides the 48 pages of actual article text. This is a great post, I wish the references could be hyperlinked.

I wish I could read French. I sure didn't expect such a distinguished work to have a four page advertisement starting on the second page! Although that's better than a paywall. ;)

In Hogan’s Heros the bombing of ball bearing factories in Düsseldorf was often a plot point. Iirc.

While the bombing succeeded in destroying the factories, the Germans simply transferred bearings from machines where they weren't particularly needed to where they were.

I'm pretty sure that sooner or later you run out of places where the bearings aren't particularly needed, not to mention the extra work in transferring makes the system slower. I think the destroying of the factories was successful in its objectives.

Like from Pachinko machines? ;)

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