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Does anyone know about the weird SE fan?
Posted by: Carboy7 on 2017-04-09 20:14:51
I was watching a video on a Mac SE, and the guy was talking about this weird "fan" (that looked a lot like a cylinder).

Apparently, it was loud and obnoxious, so Apple quietly got rid of it and used a conventional fan.

Can anyone back up this fact? (I just want to know about it. It looked cool!)untitled.JPG

Posted by: Themk on 2017-04-09 20:31:18
Yes! That is a legit fan from the factory. Only present on '87 SE analog boards. My SE/30 has one because someone swapped in an analog board from an early 87 SE.

It is nicknamed the squirrel cage fan. If you maintain them, they aren't so bad. If you let the junk build up, yeah they get loud and obnoxious. Personally I kind of like them, they also move a bit more air than the axial fan that was shipped in later units.

Posted by: bibilit on 2017-04-09 23:23:25
Yes, "Squirrel cage Fan" used to have one in an SE as well, most of them were replaced.

Posted by: BadGoldEagle on 2017-04-10 00:59:18
I want one badly. My 87 SE has the axial fan... If anybody want to do a straight swap, I'm up for it!

Posted by: Themk on 2017-04-10 06:35:14
Sorry, I want one badly too, so I will not trade! 😛

Thinking about swapping the squirrel cage fan from my '87 SE analog board into my '89/'90 SE analog board. Want to pair that little beast with low hour components on my other AB.

Posted by: Trash80toHP_Mini on 2017-04-10 20:36:19
I had no idea that this was a thing, matter of fact I never knew they switched to axial fans! My new $30 craigslist SE is squirrely, just like the one I had back in the day, heh! 😛

Seriously, it's squirrely! It's not a proper centrifugal blower (squirrel cage fan) because it doesn't have a housing or change the direction of airflow. Those are used for high pressure, high volume applications like forcing air through HVAC systems.

Forward Curve Multi-vane blower wheels are for moving large volumes of air at lower pressures. Typically selected for general ventilation or forced cooling at slower speeds.
Rodent terminology is snappier, even if inaccurate, not sure what it is really called. Here's that site, but they call it squirrely too. What the heck is that thing?

https://www.cincinnatifan.com/blower-wheels.htm

Posted by: Themk on 2017-04-11 18:06:02
squirrely is right. I kind of like it, the cylinder just kind of bangs around on its mount, lol. Someone should build a housing for one to make it a proper centrifugal blower.

Posted by: clh333 on 2017-04-11 18:41:12
I read in the Larry Pina books that this fan is not only noisier but also is associated with EMI that can affect the display.  Ferrite bead clamshell recommended for leads to video.

-CH-

Posted by: Themk on 2017-04-11 18:53:11
I think most had a ferrite bead for the video, even after the axial fan was introduced.

Posted by: RetroRik on 2019-08-20 01:39:18
I just got an Original SE but the fan fell to dust when I went to clean it. Does anyone have a squirrel fan I could have/buy off them?

Posted by: jimjimx on 2019-08-21 10:18:43
The proper term is “centrifugal fan” or “blower”, commonly used in ventilation systems.  

Posted by: jimjimx on 2019-08-21 12:51:40
https://www.dynamicfan.com/what-is-a-centrifugal-fan-used-for/

https://en.m.wikipedia.org/wiki/Centrifugal_fan

Posted by: oldappleguy on 2019-08-21 13:59:19
when apple changed fans they also changed the board on the back of the crt from horizontal to a vertical design

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