How do I use a chamber fan...tedious...sorry.

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Tatersalad2000
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Tue Aug 11, 2009 10:43 pm

I'm 50% done with my 2nd cannon. The first one being from 12 years ago.

Reading here has really helped and I plan to be launching this weekend.

I've never installed a chamber fan but it appears to be an apocalyptic mistake to not have one.

I've found plenty of info on installing....good stuff.

I just have no idea how to use it.

Obviously you want to blow the fumes out after each shot.

What about after the fuel is sprayed in? Full blast?

if so, how about just mounting the battery inside and just leaving it on the whole time?

That would avoid drilling a hole for the wires.

Is this viable aside from fussing over the overwhelming expense of 9V batteries?

Edited by jrrdw.
niglch
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Tue Aug 11, 2009 10:52 pm

You can use the chamber fan in 3 different ways:
  • *Before each shot in order to mix the fuel.
    *After each shot to vent combustion products and reoxygenate the chamber.
    *During the shot in order to produce turbulence and increase the speed of the flame front.
The first two are the most important. I'm not sure if the last one produces much of a noticable affect, but theoretically, it should also help performance.

I guess you could mount the battery inside. However, you would have to manually remove the battery from the chamber when the gun is not being used. Personally I would use a switch though.
Tatersalad2000
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Wed Aug 12, 2009 11:38 am

Okay I'll get it rigged up and see how it goes. Thanks.
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jimmy101
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Wed Aug 12, 2009 12:54 pm

If you are fueling by "squirt-n-screw" I wouldn't run the fan during fueling. Squirt the fuel, close the chamber then turn the fan on.

If you have a fuel meter, or inject with a syring through a small port then you can leave the fan running all the time.

DR (aka bigdog?), IIRC, has used those small cheap "personal" fans (hand held battery operated with foam of thin plastic safety blades) and just mounts the entire fan assembly inside the chamber and leaves it running during the entire shooting seesion.
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