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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

#111

Post by foepys »

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 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 documentaries usually simply follow the process and neutrally explain what is happening.

Re: 1937 film explains how a car differential works

#112

Post by Animats »

djbebs wrote: post #53
neogodless wrote: post #32

Earlier quoted context omitted.

Do you have a source to explains how you're describing this? I'm aware of government (financial) aid, as well as appointing government officials to "consult" and direct restructuring, but it's much less clear that it was "effectively dissolved" or that a "new" General Motors purchased assets from the old one. https://www.politico.com/story/2018/12/19/bush-bails-out-us-...

The wikipedia article is fairly extensive. https://en.m.wikipedia.org/wiki/General_Motors_Chapter_11_re...

The main GM article on Wikipedia used to make that distinction, but it was heavily edited to de-emphasize the fact that the original GM was liquidated. The original company was General Motors Corporation. That went bankrupt, and the name was changed to Motors Liquidation Company. If you were a GM stockholder before the bankruptcy, you ended up with stock in Motors Liquidation. If you were a creditor of GM, you were a creditor of Motors Liquidation.

A new company, General Motors Company, was created, and it bought the more useful assets of Motors Liquidation. Not all of them. Motors Liquidation was left to sell off unwanted plants, and such assets as GM's car collection. (GM used to have a collection of one of everything they'd made.) Today's GM is General Motors Company, much smaller than "Old GM".

Re: 1937 film explains how a car differential works

#113

Post by Reason077 »

rightbyte wrote: post #52
ernst_klim wrote: post #3

Great stuff. Making me think how simpler electrocars are: no differentials, no transmission, no complex injection machinery.

You need diff and transmission for EVs thought unless you have direct drive on two wheels.

Yes, most current EVs (including Teslas) have single-speed transmissions at each motor driving two wheels via a diff.

Some upcoming models, such as the Rivian R1T pick-up, put a discrete motor at each wheel, allowing each to be driven independently without need for a diff.

Re: 1937 film explains how a car differential works

#114

Post by bacon_waffle »

The "low-center drive" required development of hypoid gearing, versus the spiral bevel gearing used when the drive pinion axis intersects the axle axis. The strength benefits mentioned in the video come from the hypoid gearing, at the cost of efficiency.

AFAIK there isn't currently open-source CAD tooling for designing hypoids.

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

Re: 1937 film explains how a car differential works

#115

Post by benlivengood »

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.

Model S Plaid edition, in theory the top end cybertruck and the new roadster.

Re: 1937 film explains how a car differential works

#116

Post by systemvoltage »

foepys wrote: post #111
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 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…

Not sure if I agree. European YouTube channels are doing the same. It’s a general trend, not specific to American productions. The real reason is the incentives that content producers are subjected to. Notice how YouTube algorithms have promoted thumbnails to include faces. TV, documentaries and the likes are subjected to viewership and engagement metrics. Things have gotten worse over the years.

There are still a lot of great YouTube channels - Applied Science, Tech Ingredients and such. Nationality has nothing to do with this. 1970’s American television was amazing. Watch some Bell Labs videos or how Saul Bass did branding.

Re: 1937 film explains how a car differential works

#118

Post by thomasahle »

nimbius wrote: post #97

I work as a diesel engine technician for a small midwestern chain and I whip this video out in the breakroom whenever the apprentice gets an idler/pitman or diff rebuild on a large truck. So many of the guys i work with know about LSD (Limited Slip Differentials) and locking differentials/hubs, but dont entirely understand why they are needed or how they work once the wheels are back on the ground. if you really want…

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.

Re: 1937 film explains how a car differential works

#119

Post by kmstout »

RichardCA wrote: post #104
ryukafalz wrote: post #92

Earlier quoted context omitted.

Thank you so much for linking to this. I knew about many of the concepts in an abstract sense but this cemented them all together for me in an intuitive way.

This one's good too. https://youtu.be/2OP0gp9v5XM

As is this [:-|

https://www.youtube.com./watch?v=Ac7G7xOG2Ag

Re: 1937 film explains how a car differential works

#120

Post by WillPostForFood »

thomasahle wrote: post #117

The ending on lowering the differential never explained why they didn't just use front wheel drive. Can anyone fill me in?

You need to be able to steer with the front wheels, so a simple differential like this wouldn't work. You need some additional complexity to support driving and steering with the same wheels (CV axles). It just took time for the technology to become cheaper, more compact, better engineered, and paired with smaller engines.
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