One entry Cannon.

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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Redcoat
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Sun Sep 23, 2007 2:30 am

Hi all,

I know people have done this but i wasn't sure if I remembered correctly. It's not something I've dabbled in. It will be my first Combustion gun for a year.
(Except the ghetto one).

Anyway, Basically, there is one tube with a nail in it about two thirds of the way down to stop the projectile going all the way down. And one endcap on the other end and with a BBQ lighter ignition in it.

You spray the fuel into the top of the barrel and drop the projectile down and when it hits the nail you "press" the trigger and it ignites much like a normal combustion and off it goes.

Sorry if it sounds noobish, it will be my first actual combustion in a year.

Happy Spuddin'
Poo.
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frankrede
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Sun Sep 23, 2007 2:50 am

lYK OmG SND MAI Da PIx
Current project: Afghanistan deployment
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Redcoat
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Sun Sep 23, 2007 2:51 am

what? I don't understand internet talk. Something aout sending pictures what does IYK mean?
Poo.
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frankrede
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Sun Sep 23, 2007 3:03 am

Redcoat wrote:what? I don't understand internet talk. Something aout sending pictures what does IYK mean?
It was sarcasm lol, but I would like to see some pictures.
Current project: Afghanistan deployment
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Redcoat
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Sun Sep 23, 2007 3:04 am

I suck at drawing this on a diagram. Just Imagine a Piece of PVC pipe with an endcap and that endcap has an igniter in it.

You spray the fuel into the top of the barrel and drop the projectile down and ignite it.
Poo.
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frankrede
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Sun Sep 23, 2007 3:31 am

hah I get it, I have built a few with spare parts.
Current project: Afghanistan deployment
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Redcoat
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Sun Sep 23, 2007 3:58 am

cool, so it should work. I too, am building it from spare parts.
Poo.
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psycix
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Sun Sep 23, 2007 11:56 am

But when you drop the projectile 2/3 of all air (including fuel) has to slip through!
Doesnt that give problems?

But btw, please post pics/vids :)
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Redcoat
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Sun Sep 23, 2007 3:47 pm

NO I'm in the process of making it through the week. This is just a spare parts cannon I thought I'd just throw together.

@Psycix, there is a nail to stop the projectile going to the bottom.
Poo.
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veginator
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Sun Sep 23, 2007 4:30 pm

He's saying that when you drop in the projectile it will have to force alot of the air out along with the fuel and that might cause problems. Did that clear everything up. Btw if you already new that then just ignore me.
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Dornep
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Sun Sep 23, 2007 5:58 pm

I would use a threaded end cap. When you try to ram a spud down the muzzle its going to compress the air and push the spud back towards the muzzle when you remove your ramrod... That is if it has a good seal.

A removable end cap would also make venting alot easier.

BTW What size pipe or you planning on using? If it works good let me know as I have a 8ft section of 4" pipe I wannna use.... :twisted:
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Redcoat
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Mon Sep 24, 2007 2:19 am

veginator wrote:He's saying that when you drop in the projectile it will have to force alot of the air out along with the fuel and that might cause problems. Did that clear everything up. Btw if you already new that then just ignore me.
I thought he might have. Well we'll see. I was thinking of metering propane into it. (Which would probably be better).
Poo.
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psycix
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Mon Sep 24, 2007 9:17 am

I would suggest a screw-on endcap indeed!
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Redcoat
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Mon Sep 24, 2007 3:46 pm

BTW guys,
I am only making this ou of spare parts from my Pneumatic "Sniper".

So what I've got is. 50cm approx of Pressure Rated Pipe, One Endcap (Pressure Rated as well) and I have a BBQ Lighter lying around which I'm gonna disassemble to make the ignition. And I have a a nail. Or screw.
Poo.
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Redcoat
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Wed Sep 26, 2007 3:43 am

Okay everyone! It's done!!!!! Works really well too!!!!! :D :D :D :D .

Unfortunately all my tests were done in the pitch black night. aka five minutes ago. So I had to rely on sound to detect how far it was going and it sounded alright!

I think I'm gonna call it the "Party Control Cannon" because you could use it to easily control a turbulent crowd at a party. IT also looks like those Baton Round guns the Brits used In Northern Ireland.

I'll make a thread tomorrow night because I'm off school for three weeks then !!! YES!!!!!!!

sorry for double post.
Poo.
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