Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
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Deterrent
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Fri Feb 01, 2008 11:47 am
Have you guys ever had trouble with chamber fans breaking? After a few shots a corner segment of my fan broke off.
Is this normal? Do you guys use metallic fans or something? And how do you guys mount the fan in place? I shaved the corners of my fan and crammed it into the chamber. Maybe the explosion makes the chamber expand, then contract, destroying my fan? If this is the case, what would be a better way to secure the fan in the chamber?
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jrrdw
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Fri Feb 01, 2008 12:16 pm
Wow it's busted all rite! Thats the first I've seen anybody has shown. It's possible for the chamber to expand a little. You may have hit the nail on the head.
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Deterrent
- Private 2
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Fri Feb 01, 2008 1:18 pm
MaxuS the 2nd wrote:You just used a proper flimsy fan, maybe breaking the corners off to make it fit made some hairline cracks.
I seriously doubt it. The plastic was incredibly tough. And I didn't break pieces off it, I carefully sawed the extra flaps off the corners (which had nothing to do with the places at which the frame broke).
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psycix
- Sergeant Major 4
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Sun Feb 03, 2008 6:50 pm
It COULD be the expanding / shrinking chamber, but I think the fan matarial would expand/shrink aswell.
Maybe it was forced to move a lil inside the chamber, but the friction broke of one of the corners?
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TwitchTheAussie
- Corporal 5
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Sun Feb 03, 2008 6:53 pm
Id just say you got a dodgy fan my friend. Brittle.
Raise your horns if you love metal.
spudgunning is like sex, once you've tasted, you can't wait til next time.
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CpTn_lAw
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Carlman
- Staff Sergeant 2
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Sun Feb 03, 2008 7:42 pm
psycix wrote:It COULD be the expanding / shrinking chamber, but I think the fan matarial would expand/shrink aswell.
Th fan material would not be subject to the sudden increase in pressure as it does not have to contain it. the fan's shape should stay the same.
My bet is with a defect fan.
EDIT: TWITCH your back mate
Aussie spudders unite!!
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TwitchTheAussie
- Corporal 5
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Mon Feb 04, 2008 4:45 am
Yeah. Couldnt resist
Raise your horns if you love metal.
spudgunning is like sex, once you've tasted, you can't wait til next time.
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CpTn_lAw
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psycix
- Sergeant Major 4
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Mon Feb 04, 2008 5:34 am
Carlman wrote:psycix wrote:It COULD be the expanding / shrinking chamber, but I think the fan matarial would expand/shrink aswell.
Th fan material would not be subject to the sudden increase in pressure as it does not have to contain it. the fan's shape should stay the same.
Hmm your right about that.
The fan wont change size...
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rna_duelers
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Mon Feb 04, 2008 6:10 am
Is your ignition source behind the fan or in front of it?Is the fan in the front of the chamber or the rear?It should be at the rear.Because if your ignition source is behind the fan then it basically becomes a projectile within the chamber.
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rna_duelers
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Mon Feb 04, 2008 5:02 pm
That could be a cause of the damage to your fan,as the flame front pressure wave moves towards the barrel,in short.Your fan has pressure build up on one side and damaging it.
How to fix this?Move the ignition point to in front of the fan and have the fan as far back in your chamber as you can.
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Deterrent
- Private 2
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Tue Feb 05, 2008 7:27 am
rna_duelers wrote:That could be a cause of the damage to your fan,as the flame front pressure wave moves towards the barrel,in short.Your fan has pressure build up on one side and damaging it.
How to fix this?Move the ignition point to in front of the fan and have the fan as far back in your chamber as you can.
How does the pressure destroy the fan?
And isn't placing the ignition at the back better in terms of power?
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psycix
- Sergeant Major 4
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Tue Feb 05, 2008 8:03 am
Deterrent wrote:rna_duelers wrote:That could be a cause of the damage to your fan,as the flame front pressure wave moves towards the barrel,in short.Your fan has pressure build up on one side and damaging it.
How to fix this?Move the ignition point to in front of the fan and have the fan as far back in your chamber as you can.
How does the pressure destroy the fan?
And isn't placing the ignition at the back better in terms of power?
Some people believe that, but I dont , a spark gap in the middle of the chamber is the most effective, I believe.
That way you create the most effective flamefront, burning the fuel as fast as possible. Unless you use DDT....
And isnt placing the fan at the back better in terms of effectiveness and durability?
