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Question: Motor fans

Question: Motor fans

Old 04-23-2007, 03:10 PM
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Are they supposed to blow heat to the motor or from it? I've just purchased a 3racing one and it blows air away from the motor. I presumed it'd be the other way around.
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Old 04-23-2007, 03:18 PM
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Originally Posted by daveaustin5
Are they supposed to blow heat to the motor or from it? I've just purchased a 3racing one and it blows air away from the motor. I presumed it'd be the other way around.
the 3racing ones that came on the heatsink are for taking air out of the can, no to blow... usually you blow air on the enbell and take air out from the can...

hope it helps....
al
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Old 04-23-2007, 03:21 PM
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Originally Posted by rampal
the 3racing ones that came on the heatsink are for taking air out of the can, no to blow... usually you blow air on the enbell and take air out from the can...

hope it helps....
al
But the fan overhangs the endbell. It's impossible to mount it over the can. So I should try and change the direction of the fan?

I have this one:

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Old 04-23-2007, 06:05 PM
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try changing the direction, it is deas simple, just take the 4 screws out and turn the fan upside down, then replace the screws
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Old 04-23-2007, 06:30 PM
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Then replace the fan with a Much More fan. The 3-Racing fans are very weak.
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Old 04-23-2007, 06:46 PM
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to cool the motor you definitly blow air into the motor.

think about it, on a hot day do you sit in front of a fan or behind it?

unless the motor and fan is in a sealed vacuum then sucking air wont be sucking the air from the motor.
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Old 04-24-2007, 01:24 AM
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I can assure you the following is correct

Blow air into the endbell (ideally the fan will face the endbell, not be above it - see Much More for Motor fan posts)

Pull air out and away from the motor can slots


GymBeam - I can understand your theory, but we are talking about a motor and not a body. As the motor spins air is pushed away from the arm (which it is supposed to by design). As such you want to drag warm air away from the area around the motor. Below the can the air is dragged away by the car simply moving through the air, above though the fan helps move it to keep the air around the can cooler.

The reason we blow air into the endbell is to cool the brushes and comm, then this warm air is then sucked out by the impelling force of the arm.

I hope this helps explain.

And yep, 3 racing fans are very fragile, but I would simply look on any PC hardware website for a 30mm x 5mm (or 10mm) 5v fan, probably 1/2 the price of a much more !
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Old 04-24-2007, 03:14 AM
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I agree if GymBeam, you can't direct where the air comes from, but you can direct where it comes from.
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Old 04-24-2007, 04:08 AM
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Originally Posted by ILikeLinux
I agree if GymBeam, you can't direct where the air comes from, but you can direct where it comes from.
ayyyyy???? you can't direct where the air comes from, but you can direct where it comes from, well which is it dude????
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Old 04-24-2007, 04:46 AM
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it works both ways...

main difference is with proper placement pushing air onto/into the endbell can help keep the brushes and comm cooler and will help with keeping them from burning up.

if the fan is used to pull air then all it does is help cool the can and the overall temperature of the motor with no direct emphasis on the endbell/brush/comm area...

this is all assuming the strength of the fan has at least a small increase over normal convection from the speed of the car...
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Old 04-24-2007, 04:55 AM
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sucking air wont be effective in an open enviroment. it would be barely drawing any heat away from the comm, when the fan is about 1 inch from it.

look at Novaks ESC, thier fans blow air into the esc dissapating the heat. i think novak knows a thing or two to keep thier esc's cool.

anyway, do a few tests with a temp gun, you will get your answer.
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Old 04-30-2007, 12:31 PM
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you can move that fan forward so it is over the can, just remove all the screws on the fan and the ones over the heatsink, move it forware and replace the screws
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Old 04-30-2007, 09:11 PM
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I definitely understand where some people are coming from. In theory it's probably a better solution to have the air sucked from the motor because of the spinning armature. BUT in reality I'm certain that if you were to do a few tests with a temp gun you'll find that blowing air onto the endbell will be much more effective, at least with the setup shown above. For the other solution to work properly it would need to be sealed against a vent on the motor in which it would then suck the warm air out.
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Old 04-30-2007, 11:01 PM
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Originally Posted by Boosta
ayyyyy???? you can't direct where the air comes from, but you can direct where it comes from, well which is it dude????
Opps, just noticed the mistake :-P
Should be "you can't direct where the air comes from, but you can direct where it goes."
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Old 04-30-2007, 11:39 PM
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Originally Posted by Kevin CBR
Then replace the fan with a Much More fan. The 3-Racing fans are very weak.
I bought one of these, the fan was jammed to begin with, when I took the screws out the whole thing virtually fell apart in my hands.

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