All fans are definitely not created equal. I tried a black case fan, it works on everything but the one huge HD magnet I have.....so I'll most likely use it unless I can find a 120mm.
I also tried a pci blower-style exhaust fan that I have. This thing would fling the huge HD magnet off of it.
It is only 12v and 0.16A, but is uses ball bearings and is a bit beefier....perhaps I'll use it if the other won't work through the housing.
I am planning on picking up the parts I am missing on Friday. I'll update after it gets finished.
__________________ MT
------------------------------------------------------------------------------------------
Save me, O God! For the waters have come up to my neck. - Psalm 69:1
Since I will be scavenging an old pc tower for parts anyways, could I use the power supply from that in lieu of the cell charger type? If so, I am assuming the rheostat would then let me fine tune how much "oomph" I give the fan...
I haven't tried using a computer power supply. I would expect the output to be a little higher than what is required to run the fan.
Thus far, I have used:
Cell Phone Chargers, Bluetooth Headset chargers, and Linksys Modem Power Supplies.
__________________
I'd rather have a bottle in front of me, than a frontal lobotomy.
--Tom Waits
You can't be a real country unless you have a beer and an airline - it helps if you have some kind of a football team, or some nuclear weapons, but at the very least you need a beer.
--Frank Zappa
Since I will be scavenging an old pc tower for parts anyways, could I use the power supply from that in lieu of the cell charger type? If so, I am assuming the rheostat would then let me fine tune how much "oomph" I give the fan...
If it is a very old computer it would be easy enough, if it is just old and is a ATX power supply then there are a couple pins you have to short to make it work, otherwise the power supply doesn't think it is connected to a motherboard and wont turn on.
I got all the parts for this and just spent some time in the garage putting it together. Unfortunately I cannot get the fan to speed up and slow down. One speed. I've got it wired properly I believe, but the speed control is a no go. Any suggestions?
__________________
Baby, to a hammer everything looks like a nail...
If you are getting voltage to your fan, and it is wired through your potentiometer, I would make sure that you have your power output or "load" from your power switch going to the center pin of your potentiometer, and the power lead from your fan going to your right pin of the potentiometer.
Please note, when I say "right pin" i'm assuming you are looking at it from the pin side and not the "knob" side
__________________
I'd rather have a bottle in front of me, than a frontal lobotomy.
--Tom Waits
You can't be a real country unless you have a beer and an airline - it helps if you have some kind of a football team, or some nuclear weapons, but at the very least you need a beer.
--Frank Zappa
I started building one of these a while back (based on another thread) with similar parts. The only problem I noted was that the rheostat didn't seem to give much variability as far as speed control goes. For a third to half of the range of the rheostat the fan doesn't move. Turn it a little further and the fan comes on and jumps up to what appears a decent RPM, but turning it all the way only increases the fan speed maybe 15-20%. I'm not particularly electrically inclined, so I'm wondering if someone might suggest ways to correct the problem.
One thing to mention: this happened without any load on the fan. Would a stir bar in a flask full of liquid provide resistance to make the speed more controllable? I never got around to finishing it so I can't test the theory.
__________________ So long, and thanks for all the beer...
Tap 1: Empty Tap 2: Zippo Tap 3: Nada Tap 4: Man... I gotta get brewing Bottles: Dust
Inside a starter, there will be more resistance on the stir bar than when you try it out with water. You can go with a higher rated rheostat and try that out to see if it can give you a more variable speed. The rheostat is essentially a variable ohm resistor. Another factor is the power supply you are using. Most computer fans are rated at 12 volts DC, while most cell phone chargers are rated at 5-6 VDC.
__________________
I'd rather have a bottle in front of me, than a frontal lobotomy.
--Tom Waits
You can't be a real country unless you have a beer and an airline - it helps if you have some kind of a football team, or some nuclear weapons, but at the very least you need a beer.
--Frank Zappa
__________________
I'd rather have a bottle in front of me, than a frontal lobotomy.
--Tom Waits
You can't be a real country unless you have a beer and an airline - it helps if you have some kind of a football team, or some nuclear weapons, but at the very least you need a beer.
--Frank Zappa
Linear Mode
