Can case fans be 'reversed'?

[Nox]

I bought a couple Artic cooling 120mil fans from Directron, and when I recieved them, I find the they are hooked directly to the shrouds that keep your fingers from getting bitten while its running. My question is can they be effectively put on "reverse" since the shroud is on the wrong side that I want the thing to blow.
Will I wreck the fan by switching the pos and neg wires in the connector?
Given, its only 10 dollar fan but I want to have an idea of what I am up against.
LINK: http://www.directron.com/acf12.html
And yea, I read that mounting to the front is not possible....I dont care, I'll make it possible LOL
Thanks!

[AKA_RA]

i think if you switched the polarity of the wires, itll prolly just make the motor spin backwards, and since the blades are angled to blow air one way, itll most likely have very little airflow spinning in reverse, but if i were you id get a second opinion on that

[Short Modder]

You could just make a custom shroud for the other side.8) By a custom shroud, I mean a shroud to fit your mod or something like that.;)

[Omega]

i think if you switched the polarity of the wires, itll prolly just make the motor spin backwards, and since the blades are angled to blow air one way, itll most likely have very little airflow spinning in reverse, but if i were you id get a second opinion on that



uhhhh, the blades can work either direction.

go ahead. try it.

[Cevinzol]

uhhhh, the blades can work either direction.
depends on whether the fans are air foils (like airplane props) if so then reversing them won't create lift (Bernoulli's principle).

[Omega]

crap what was bernoillis principle agian


i've seen fans reversed before, and it worked just fine =p

[Cevinzol]

It means if the fan blades are shaped like a airplane wing. As the air flows over the top it creates less pressure (because its moving faster - longer distance to travel) this creates lift.

In a propeller/fan blade the 'lift' translates into trust or air flow.

personaly that grill looks pretty generic. I'd just remove/dremel the grill, turn the fan around and put a cooler looking gaurd on to fit my mod.

[xmastree]

i think if you switched the polarity of the wires, itll prolly just make the motor spin backwards, I doubt it. All PC fans are brushless motors, which basically means they use electronics and four salient poles to create a spinning field, which drags the rotor round. Reversing the supply might not damage it, but it certainly wouldn't work.

http://en.wikipedia.org/wiki/Brushless_motor

[Cevinzol]

Recently, an increase in the popularity of electric-powered model aircraft has spurred demand for high-performance BLDC motors. Many hobbyists have begun salvaging BLDC motors from scrap CD/DVD-ROM drives, refurbishing them for use in radio controlled planes. This has led to increased direct consumer-availability of DIY (do-it-yourself) motor kits, for use in radio-controlled vehicles. BLDC motors sold as parts kits allow the buyer to save money through additional assembly work.
Oh I can see it now... all those old optical drives strapped to the top af cases...

Flying PC mods!

[dgrmkrp]

...these fans don't work in reverse.. just tried it.. they don't spin.. because the coil windings are made to work one way only..
..i'm not sure what you're trying to do, but if you want to put the fan in the front as an intake (which would be impossible 'cause the manufacturer says they are ment as exhausts... yeah,right) you cam just mount it on the other side..outside of the box, insinde the front bezel.. if there is room..

basically, you can't reverse the motor, but you can reverse the fan placement..