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1937 film explains how a car differential works

roadandtrack.com

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Re: 1937 film explains how a car differential works

#131

Post by elihu »

Reason077 wrote: post #99

Interesting fact I learned from this video: early cars were one -wheel-drive!

I was surprised by that as well, though in retrospect it makes sense.

I wonder if such vehicles even had a transmission, or if that was a technological advance that came later? And if, before differential car axles were invented, anyone tried solving the same problem by driving two wheels with separate engines?

With modern electric vehicles that lack a transmission, having a separate motor for each drive wheel seems like a reasonable thing to do now. I assume someone's already built such a thing; the Cybertruck is planned to have a 3-motor variant, though I don't know if two of the motors will share a differential or if they'll just each go to a separate drive wheel. Also the Rivian might have separate motors per wheel, I'm not sure.

Re: 1937 film explains how a car differential works

#132

Post by thr0w__4w4y »

mattmaroon wrote: post #127
thomasahle wrote: post #118

Earlier quoted context omitted.

I watched those two other videos, the second one twice, but I still don't really understand them. The 1937 video clicked perfectly on the first viewing.

The first video explains differential locks. Basically with an open differential all power would be routed to a wheel that’s getting no traction (for instance if it’s on ice). A differential lock closes it, so it’s as if there were no differential, so both wheels on the axle will turn at the same speed. This is bad if you’re on a normal road (obviously, since that’s why differential were invented) but great in low tr…

Yep, until I'd done off-roading, I never understood why my uncle told me (when driving his vehicle, which had the ability to lock the diff) - "Never ever use this on pavement / normal driving". I obeyed him, but I always thought he was full of it, until I had the money & time & inclination to work on cars, and I learned what was really going on.

"Aaaahhhh... so that's why he told me that..." Thanks Uncle Bill!

Re: 1937 film explains how a car differential works

#133

Post by GekkePrutser »

mattmaroon wrote: post #127
thomasahle wrote: post #118

Earlier quoted context omitted.

I watched those two other videos, the second one twice, but I still don't really understand them. The 1937 video clicked perfectly on the first viewing.

The first video explains differential locks. Basically with an open differential all power would be routed to a wheel that’s getting no traction (for instance if it’s on ice). A differential lock closes it, so it’s as if there were no differential, so both wheels on the axle will turn at the same speed. This is bad if you’re on a normal road (obviously, since that’s why differential were invented) but great in low tr…

Yeah I believe this is how modern cars with traction control work, they brake the slioping wheel so the one with contact can get the traction.

At least this is how it was explained to me by my mechanic friend

Re: 1937 film explains how a car differential works

#134

Post by geoduck14 »

dmix wrote: post #95
tqi wrote: post #89

The lack of background music and pace is really interesting to me. Compared to a typical "how it's made" video [1] (which I feel has a similar level of detail), this video feels significantly more digestible. Those moments of silence feel totally alien and out of place in today's style, but I think contributes positively to my ability to understand and process the information. [1] https://youtu.be/8gno0_emzo8

That's a good observation. There is a slow pacing but when it's quiet your mind is still working so it's not 'boring' time. It's just like in sports now where someone has to be rambling about something the entire game, even though you're watching it. It's still useful, often to find out which player shot or for the added excitement with the crowd. But they ALL feel the need to fill dead space the entire show which I…

If the losing team wants to win this game, they are going to need to score more points.

https://i.pinimg.com/originals/a8/21/10/a82110b6d53e4089a33e...

Re: 1937 film explains how a car differential works

#135

Post by b0ner_t0ner »

Animats wrote: post #105

Yes, "Around the Corner", one of many Jam Handy films made for Chevrolet. They're all on the Internet Archive, where they can be seen without ads.[1] There's a whole series. "Spinning Levers" (transmissions), "Down the Gasoline Trail" (fuel), "Just a Spark" (ignition), "Tough Friends" (steel), "No Ghosts" (frames), and more. [1] https://archive.org/details/0141_Around_the_Corner_M00267_08...

Somebody should use the latest AI libraries available to upscale all these to 4K and maybe even colorize them.

Re: 1937 film explains how a car differential works

#136

Post by [deleted] »

throwaway0a5e wrote: post #130
foepys wrote: post #111

Earlier quoted context omitted.

That's mostly American television. I cannot watch American documentaries because everything is being hyped as largest, heaviest, most expensive, deadliest, etc. and is being narrated in the same sensationalist tone. I cannot convey the tone by text but you certainly know what I mean. The interesting details always get lost because the hype must be there to keep people watching after the next ad break. European docume…

I've been watching the Free Documentary (I think that's their name) channel on Youtube. They're all European documentaries. They over hype stuff and design around commercial breaks too.

[deleted]

Re: 1937 film explains how a car differential works

#137

Post by bjterry »

Dirlewanger wrote: post #129
foepys wrote: post #111

Earlier quoted context omitted.

That's mostly American television. I cannot watch American documentaries because everything is being hyped as largest, heaviest, most expensive, deadliest, etc. and is being narrated in the same sensationalist tone. I cannot convey the tone by text but you certainly know what I mean. The interesting details always get lost because the hype must be there to keep people watching after the next ad break. European docume…

BBC documentaries (especially the nature ones) do a lot of obnoxious foley work.

Also, a very dangerous drinking game is to watch BBC's Planet Earth and have a drink every time they use a superlative ("most," "biggest," "fastest," etc). So that is also definitely not an exclusively American phenomenon.

Re: 1937 film explains how a car differential works

#138

Post by jimmaswell »

lopmotr wrote: post #54
harperlee wrote: post #39

Earlier quoted context omitted.

Why is that? Tesla Model 3 for example uses 1 or 2 motors, not one per wheel, so they still need to add variable speed to left vs. right wheels, right?

I don't understand either. Somebody else made the same comment but typical electric cars still have diffs. Examples include Chevy Volt, Nissan Leaf, and Tesla Model 3, Tesla Model S. Where are the electric cars with independent left/right drive motors? Even cheap toy electric R/C cars have differentials.

What's the point of a differential for wheels that aren't driven? Why even connect them at all?

Re: 1937 film explains how a car differential works

#140

Post by ardy42 »

tqi wrote: post #89

The lack of background music and pace is really interesting to me. Compared to a typical "how it's made" video [1] (which I feel has a similar level of detail), this video feels significantly more digestible. Those moments of silence feel totally alien and out of place in today's style, but I think contributes positively to my ability to understand and process the information. [1] https://youtu.be/8gno0_emzo8

> The lack of background music and pace is really interesting to me. Compared to a typical "how it's made" video [1] (which I feel has a similar level of detail), this video feels significantly more digestible. Those moments of silence feel totally alien and out of place in today's style, but I think contributes positively to my ability to understand and process the information.

I think that's because the older movie is an actual educational movie, while the video you linked is really pseudo-educational entertainment. An educational video has the goal of leaving the viewer with actual understanding of something, while the pseudo-educational video only cares to vaguely tickle the viewer's curiosity, and is fine to leave them nearly as ignorant as when they started. While the two movies may have a "similar level of detail," the educational video focuses on fully explaining a specific problem and solution, while the pseudo-educational video only vaguely skims through the high-level steps of some manufacturing process and barely even explains what the product is for.

http://www.engineerguy.com/ makes educational videos similar to this 1937 movie on a lot of similar topics.

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