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1937 film explains how a car differential works

roadandtrack.com

11–20 of 148 posts

Re: 1937 film explains how a car differential works

#11
The working is explained in a step-by-step manner that makes learning easy. This is characteristic of old instructional films. The other characteristic is the assumption that viewers will sit through tiresome material at the beginning and the end. Still, the 2/3 in the middle is clear and compelling.

Re: 1937 film explains how a car differential works

#14
The style in those old films is so relaxing and pedagogically great.

Has anyone else noticed that today's educational content intended for adults increasingly uses a format that was regionally only used for very young children? There is almost always personality emoting and doing accidentally on purpose funny things and laughing, exaggerating everything to keep people engaged.

Re: 1937 film explains how a car differential works

#15
post #10

Video says nothing about forces, however. With this explanation it seems that if one wheel gets slightly stuck, the other wheel gets all the force, causing a dangerous spinning.

> With this explanation it seems that if one wheel gets slightly stuck, the other wheel gets all the force, causing a dangerous spinning.

This is how a (open) differential behaves, though a spinning wheel isn't so much dangerous as ineffective. This limitation can be overcome using a locking differential or a limited-slip differential, or a traction-control system that selectively applies brakes to a spinning wheel to simulate a limited-slip differential.

Re: 1937 film explains how a car differential works

#16
post #10

Video says nothing about forces, however. With this explanation it seems that if one wheel gets slightly stuck, the other wheel gets all the force, causing a dangerous spinning.

In the real world momentum dampens how quickly power is transferred between wheels. Further, real world engines have limited RPM ranges which generally don’t damage freely spinning tires.

So, while such simple differentials can get stuck fairly easily, they also work surprisingly well. The obvious trick is to apply some breaking power to the spinning wheel to then apply force to the stuck one, thus traction control. Or to just lock a differential when bouldering etc. More complicated mechanical systems can always provide some power to both wheels, but they aren’t actually necessary.

Re: 1937 film explains how a car differential works

#17
post #10

Video says nothing about forces, however. With this explanation it seems that if one wheel gets slightly stuck, the other wheel gets all the force, causing a dangerous spinning.

Not so much dangerous as useless. That’s why Positraction was invented. And why locking differentials are a thing.

Re: 1937 film explains how a car differential works

#18

I remember playing with a differential engine in those Lego gear sets many many years ago. When you have a bunch of the pieces lying around and free time, you'll probably accidentally make a differential too. As for this video itself, I've seem it a few times, and it still really does amaze me how much care was put into this. I assume the video is government funded, and it kind of makes me sad to realize that they ha…

> government funded

The video was made by the Jam Handy organization. They did videos for several car companies, and sometimes a consortium of them, is my understanding https://en.m.wikipedia.org/wiki/Jam_Handy

Re: 1937 film explains how a car differential works

#19
post #14

The style in those old films is so relaxing and pedagogically great. Has anyone else noticed that today's educational content intended for adults increasingly uses a format that was regionally only used for very young children? There is almost always personality emoting and doing accidentally on purpose funny things and laughing, exaggerating everything to keep people engaged.

Person-to-person interactions have changed dramatically since those days. Western culture had a sense of duty and progress that is now questioned by the postmodern intellectual elites. The emphasis today is on "enjoying yourself" in your own bubble, and debating "grand moral standards" is even ridiculed.

Re: 1937 film explains how a car differential works

#20
post #5

How would films like this be consumed in the 30’s? Would it be shown in theaters before a feature film?

Military conscripts who were assigned to motor maintenance

> Military conscripts who were assigned to motor maintenance

The OP was asking how people might watch a video like this, not who is watching it. In 1937 broadcast television was relatively new and few people owned a tv. For example, the wikipedia page for TV in 1937 notes that by the end of that year 2,121 TVs had been sold in England:

https://en.wikipedia.org/wiki/1937_in_television

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