Combustion spud gun problem

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.
da007man
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Sun Apr 24, 2011 9:05 am

If you do, it would be a very good idea to install a chamber fan as well to aid in venting the chamber.
How do you install a chamber fan? :P
da007man
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Sun Apr 24, 2011 9:29 am

:wink:
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mark.f
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Sun Apr 24, 2011 8:00 pm

You know, it's rather funny, but simply Googling "chamber fan" returns the first three pages on AdvancedSpuds, Burnt Latke, and the SpudWiki, with every image result on the Web search tab being related.

:wink:
da007man
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Mon Apr 25, 2011 4:03 am

Cool thanks.... Gotta love google ;)
BTW, I now know the right dosage for my chamber, and then I duct tape my end cap for security. It now shoots every time and the potato blows up on target 350 feet away :)
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Fnord
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Mon Apr 25, 2011 6:42 pm

Err... Normally I'm all for the use of ducttape, but this time I think You may want to invest in a proper cleanout cap at some point.
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da007man
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Wed Apr 27, 2011 1:53 pm

Yeah don't worry. It's just that school started again so I'll wait for the next vacation to continue working on it
jsefcik
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Wed Jun 08, 2011 2:42 pm

Hopefully this is the right area to post this, I was looking to build a combustion cannon using 3 inch pipe with a rifled 1.5 inch barrel, any idea on how long to make both parts? I only have 3 feet of the 3 inch and 1.5 I can get more if I need it

DONT UNDERSTAND THESE RATIOS IVE SEEN
jsefcik
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Thu Jun 16, 2011 7:40 pm

What length should me pipe be for a combustion cannon using 3 inch pvc for chamber and 1.5 inch for barrel? How long should my barrel and chamber for a air powered cannon using 4 inch pvc for chamber and 1.5 inch pvc for barrel(golf ball shooter? please help
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saefroch
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Thu Jun 16, 2011 8:55 pm

Don't rifle a spudgun barrel. It's useless. JSR can bombard you with links to rifled barrels that have demonstrated no effect, but I am too lazy to do so.

There are general ratios thrown about for chamber volume to barrel volume, but really a longer barrel or larger-volume chamber is better in almost all cases.

It'd be nice if you didn't hijack a thread. :wink:
jsefcik
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Fri Jun 17, 2011 9:44 pm

Like how long should my barrel and my chamber be for a combustion cannon? Im using 3 inch pvc for my chamber and 1.5 for my barrel.
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saefroch
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Fri Jun 17, 2011 9:46 pm

In my opinion, as long as you're comfortable. :wink:
jsefcik
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Wed Jun 22, 2011 12:19 pm

I've been given some tips that even though a combustion chamber might be small, it can still pack a punch and send them spuds flying , is this true
I was told if a have a 1 1/2 chamber and 42 inch barrel, with this I was told it will still send spuds flying? True or False?
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saefroch
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Wed Jun 22, 2011 5:51 pm

Those numbers cannot tell me anything about performance, because they are lengths, not volumes. Advanced combustions can be modeled in HGDT by setting the mix number to 1.
jsefcik
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Wed Jun 22, 2011 9:28 pm

huh? you lost me bud,I didnt understand this part( Advanced combustions can be modeled in HGDT by setting the mix number to 1.)

PLease explain
jsefcik
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Wed Jun 22, 2011 9:55 pm

Thanks you so much, helps when you look into it more, just ignore my other post guys
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