chamber fan question

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colty-bear
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Wed Jul 15, 2009 8:15 pm

i am putting in a chamber fan and making a powerbox if i use 5 9 volt batteries how long will it run the fan?
it that too many?
please reply
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spudtyrrant
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Wed Jul 15, 2009 8:16 pm

colty-bear wrote:i am putting in a chamber fan and making a powerbox if i use 5 9 volt batteries how long will it run the fan?
it that too many?
please reply
well lets see a average fan is 12 volts so if you wire 5 9 volts thats 45 volts wayyyyy to much you only need 1 maybe 2 if you want it to go really fast
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colty-bear
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Wed Jul 15, 2009 8:22 pm

ill use 1 then how long will battery last?
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spudtyrrant
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Wed Jul 15, 2009 8:24 pm

colty-bear wrote:ill use 1 then how long will battery last?

if you run it continually probably about 4 hours if you only run it when you need it maybe 500shots
ralphd
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Wed Jul 15, 2009 8:26 pm

If you wire two nine volt batteries in series and wire them in parallel to another two in series that will give you eighteen volts with more available capacity. The batteries will last longer.
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colty-bear
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Wed Jul 15, 2009 8:40 pm

how many millimeters are in a 3" pipe?
ill just get a comp fan off ebay
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jimmy101
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Wed Jul 15, 2009 11:28 pm

colty-bear wrote:how many millimeters are in a 3" pipe?
ill just get a comp fan off ebay
3" is about 75 mm, but the largest square that'll fit in a 3" circle is about 2.1" (52mm) on edge. Try to find a 40mm or so fan. Check PC repair places and your friends for an old computer. CPU fan works well in a chamber. Usually they are 12V but work fine on 9V.

Surplus places often have small fans for cheap, like All Electronics:
http://www.allelectronics.com/make-a-st ... FAN/1.html
http://www.allelectronics.com/make-a-st ... FAN/1.html
http://www.allelectronics.com/make-a-st ... FAN/1.html
http://www.allelectronics.com/make-a-st ... FAN/1.html
For two to three bucks each, $7 total shipping regardless of the number (up to a point).

It's a good idea to buy at least two, you'll save on shipping and fans sometimes get trashed in the chamber.
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colty-bear
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Thu Jul 16, 2009 9:10 pm

hey i have decided to get a 70mm and shave it down but all the fans i have found have a 3 or 4 pin cord i want 2 wires but is there a way i can modify it to run on just 2 cords
or can someone post a link to a 70mm 2 lead fan?
please
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inonickname
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Thu Jul 16, 2009 10:52 pm

colty-bear wrote:all the fans i have found have a 3 or 4 pin cord i want 2 wires but is there a way i can modify it to run on just 2 cords
The third cable is to control speed. Just try hooking up two of them (if it doesn't work, try the others) and it should work.
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jimmy101
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Fri Jul 17, 2009 4:07 pm

colty-bear wrote:hey i have decided to get a 70mm and shave it down
A smaller fan will probably work better. It won't vent the chamber as fast but will probably mix better.

A smaller fan puts less material in the chamber which reduces the heat loss. A 70mm fan has a heck of a lot of surface area.
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colty-bear
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Fri Jul 17, 2009 7:45 pm

sorry too late :( i just got a 70mm 2 lead fan yesterday
My first 300 spud bux.
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