How to define the best mix??

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.
Hugeapnic
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Fri Mar 15, 2013 12:30 pm

I operate my spudgun with deodorant.
I can inject the gas with a microcontroller, so I get very reliable results.

But how to define the best mix??
I thought if it fires, the leanes tmix is the best.
But it is not. If I inject more gas, the power goes up.

Is there a way to find the best mix??

Just go for the loudest bang??
How do you define your settings??
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jackssmirkingrevenge
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Fri Mar 15, 2013 12:47 pm

Read this and stop using deodorant ;) (as fuel I mean :D)

http://www.spudfiles.com/spud_wiki/inde ... n_Spudguns
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Labtecpower
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Fri Mar 15, 2013 1:05 pm

Thank the kind sir Jack for this :)

[youtube][/youtube]

Works perfectly every time I try!
Read this and stop using deodorant :wink: (as fuel I mean :D )
If you spray your armpits with deodorant and then hold a lighter near them, wouldn't it be the perfect antiperspirant? :D
natas
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Sun Mar 24, 2013 5:31 pm

if u shoot at night, and you see flames coming out of your barrel, tou are using too much fuel.
in a perfect world, the chamber should run out of fuel at the same time as the "potato" leaves the barrel.

too lean, and you get a vacuum before the projectile leaved the barrel.
too much fuel, and you do not get full power out of your chamber volume.

nightshooting is the easy way too check the fuel mix.
To make dreams come true, u must wake up.
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Technician1002
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Mon Mar 25, 2013 3:28 am

^^^ I thought if the barrel was too short, you get a bigger muzzle flash. If the barrel is too long, you get none. You do want the spud to leave the barrel while there is still pressure behind it so it is not slowing before it exits. Too much fuel results in a slower burn and a slower launch. It does not always result in a large muzzle flash.
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Labtecpower
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Mon Mar 25, 2013 3:34 am

I would suggest that you download HGDT and fiddle with some different sizes until you're happy. It'll also give you the amount of fuel to inject.
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