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Early electric fans

earlyfans.blogspot.com

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Re: Early electric fans

#41

Post by lnanek2 »

frosted-flakes wrote: post #31
everybodyknows wrote: post #27

Earlier quoted context omitted.

> Why cap guns? Who knows. I know, because 11-year-old me owned one, back when selling them was legal. The reason is nostalgia, or a yearning for the brightness of the world we knew then. Artifacts bring the memories back, in a sweet flood. Experimentation revealed ways in which cap gun tech could be abused. We wanted a louder pop, so how about folding over the tape of caps to double up? Possible, but tends to jam. F…

Wait, they're illegal now? Where? I had those growing up in Canada in the early 2000s. If I remember right, we got them at the dollar store. And yes, I remember hitting a whole ring at once with a hammer.

Probably for the best here in the US. Police here jump on any excuse to use deadly force and hearing a bang sound from a cap gun would likely invite a hail of real bullets. Did you see a 9 year old girl was pepper sprayed recently? And that 75 year old man shoved over, banging his head on concrete, and bleeding on to the streets from it for having an imaginary police scanner? And the girl trying to give a guardsman flowers getting a direct hit from a flash bang in return? Imagine if one of them had a cap gun...not pretty.

Re: Early electric fans

#42

Post by mikestew »

freefal wrote: post #4

Wow, the combination of those heavy metal blades and the sparsely placed safety bars definitely doesn't look finger friendly!

It was not a finger-friendly time for technology. Here, take a look at the Farmall tractor/buzzsaw combination that is quite similar to the one I grew up cutting wood with (and probably only slightly newer than some of those fans) :

http://sketchesofalaska.blogspot.com/2012/08/farmall-tractor...

I have all fingers and toes, but you couldn't sell that shit today without getting sued out of existence.

Re: Early electric fans

#43

Post by csharptwdec19 »

lnanek2 wrote: post #41
frosted-flakes wrote: post #31

Earlier quoted context omitted.

Wait, they're illegal now? Where? I had those growing up in Canada in the early 2000s. If I remember right, we got them at the dollar store. And yes, I remember hitting a whole ring at once with a hammer.

Probably for the best here in the US. Police here jump on any excuse to use deadly force and hearing a bang sound from a cap gun would likely invite a hail of real bullets. Did you see a 9 year old girl was pepper sprayed recently? And that 75 year old man shoved over, banging his head on concrete, and bleeding on to the streets from it for having an imaginary police scanner? And the girl trying to give a guardsman f…

Yep.

This is also a big part of why 'Light guns' for video game consoles in the US looked more and more like a prop from Buck Rogers through the 90s

Re: Early electric fans

#44

Post by lqet »

jetrink wrote: post #24
lqet wrote: post #20

> A sheet brass disk in front of the fan was acted upon by the air from the fan causing the fan to oscillate back and forth Is this an accurate description? Here is such a fan in action: https://www.youtube.com/watch?v=Cm7DFuGaujg It seems to work because the brass disk is blocking the air stream on one side, so the other side of the fan acts as a jet engine to rotate it, which is actually really clever.

Wow, that is more violent than I expected! I think both effects are at work. Thought experiment/hypothesis: If you detached the plate and merely held it in front of the fan blades, I think the fan would still rotate due to the decreased airflow on one side of the fan, but it would rotate less quickly since the force that moving air is applying to the plate would no longer be acting on the fan.

Yup, I posted the original comment to quickly, the airflow indeed also pushes the brass disk forward, thus rotating the fan! An extremely clever solution that seems to be very easy and cheap to manufacture.

Re: Early electric fans

#45

Post by mattkrause »

scottlocklin wrote: post #37
mattkrause wrote: post #36

Earlier quoted context omitted.

The cheapest one is $20,000!

I thought they were too much when I was in grad school in the 90s and you could find them on ebay for $500.... $500 for a goddamned fan! Well, it's not like they made more of them since then, and many have been parted out or thrown away. Those pancake fans are really cool!

Oh, no argument that they look cool. I was just expecting the price to be a lot lower!

Does anyone make good-looking modern reproductions?

Re: Early electric fans

#46

Post by scottlocklin »

mattkrause wrote: post #45
scottlocklin wrote: post #37

Earlier quoted context omitted.

I thought they were too much when I was in grad school in the 90s and you could find them on ebay for $500.... $500 for a goddamned fan! Well, it's not like they made more of them since then, and many have been parted out or thrown away. Those pancake fans are really cool!

Oh, no argument that they look cool. I was just expecting the price to be a lot lower! Does anyone make good-looking modern reproductions?

Nope. But for $20k you could probably pay a skilled machinist to make you a couple of them.

Re: Early electric fans

#47

Post by [deleted] »

jetrink wrote: post #24
lqet wrote: post #20

> A sheet brass disk in front of the fan was acted upon by the air from the fan causing the fan to oscillate back and forth Is this an accurate description? Here is such a fan in action: https://www.youtube.com/watch?v=Cm7DFuGaujg It seems to work because the brass disk is blocking the air stream on one side, so the other side of the fan acts as a jet engine to rotate it, which is actually really clever.

Wow, that is more violent than I expected! I think both effects are at work. Thought experiment/hypothesis: If you detached the plate and merely held it in front of the fan blades, I think the fan would still rotate due to the decreased airflow on one side of the fan, but it would rotate less quickly since the force that moving air is applying to the plate would no longer be acting on the fan.

[deleted]

Re: Early electric fans

#48

Post by perilunar »

lqet wrote: post #44
jetrink wrote: post #24

Earlier quoted context omitted.

Wow, that is more violent than I expected! I think both effects are at work. Thought experiment/hypothesis: If you detached the plate and merely held it in front of the fan blades, I think the fan would still rotate due to the decreased airflow on one side of the fan, but it would rotate less quickly since the force that moving air is applying to the plate would no longer be acting on the fan.

Yup, I posted the original comment to quickly, the airflow indeed also pushes the brass disk forward, thus rotating the fan! An extremely clever solution that seems to be very easy and cheap to manufacture.

> the airflow indeed also pushes the brass disk forward

The force on the disk is caused by an opposite force on the fan blades, cancelling them out (since they are connected by the frame and the bearings), so it cannot cause the fan to rotate.

The rotation is due simply to unbalanced thrust from the fan. The unimpeded side produces more thrust than the impeded side, so the fan turns to that side.

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