STAG-2

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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FiveseveN
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Wed Mar 29, 2006 11:45 am

Dude, seriously :) :
1. How can the flame from the combustion go through two ball valves (on the propane meter), the tiny hole of the regulator and the tank's pin valve?
2. Even if it would, it wouldn't explode since there's no oxidizer in the tank, only fuel. We've been through this a dozen times.

And on the carbide cannon issue: BLB is right. I've seen ghetto carbide cannons made from tin cans or drain pipe that worked just fine. I've even ignited acetylene in a PET bottle and it didn't even bend it. There's just not enough time for heat to do any damage, 'specially since acetylene burns faster than propane.
However, since the pressure peak is higher and DTD is more likely to occur, I would only recommend it in short metal chambers, NOT PVC.
pyrogeek
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Sat May 13, 2006 10:45 pm

boilingleadbath wrote:Spudshot, that response to that question has been shown to be wrong so many times... well, I'll leave out the inferences one might make about you.

Anyway, propane tourches are pretty effective at burning through PVC. Odd that we can use propane as a launcher fuel when that's true...
You can burn yourself with a lighter if you leave your hand in the flame too long, but if you pass it through without stopping, it will just get a little ash on your hand. Same idea, it just isn't being heated long enough to matter. I have messed around with my little combustion guns made from pill bottles and pens and after a while the plastic begins to get a little softer, but that was from repeted firing. I use butane in them by the way, I dispense it from a modified butane cartridge from a stick lighter. I just turned the little lever thing to release the gas around to make it easier to release.
pvc
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Mon Jun 05, 2006 10:56 am

boom_o_matic wrote:Awesome gun but one problem...ABS is not pressure rated. It could weaken and explode. I'm not being critical but that is very dangerous.
ya im pritty shure that would be bad. last time i used one of thoes tanks it chought on fire. dident explode "untill 6 hours in"but was shooting out 3 foot flames. lol be carful. and dont do drugs or else
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)DEMON(
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Mon Jun 05, 2006 11:10 am

PostPosted: 05/13/2006 20:45 PM stop kicking up posts..... :!: ...please
Forever dreaming...
kris
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Sun Jun 25, 2006 6:59 pm

oxy-acetylene would be good for a mortar because the barrel is shorter :idea:
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ProfessorAmadeus
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Sun Jun 25, 2006 7:12 pm

ok you go ahead and try that and when your burning in hell from your stupidity tell me if that works in a pvc cannon. did you not read any of the above post talking about how a STEEL cannon might not even be able to hold the pressure.
pvc
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Sat Jul 29, 2006 10:35 pm

spudshot wrote:no its not, ABS has been use MANY times in combustions, and aside from high powered fuels i've never heard of one exploding, there's not much danger there if you built it right
if u build it right it wont kill, its point less kids the wanna make it quick and dont care if it is done right or not
spud man
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Tue Aug 01, 2006 3:48 pm

The propane tank wont blow up we all ready talked about that.
Viper
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Mon Sep 11, 2006 11:44 am

not really clean lookin' and you need a longer barrel, but a nice gun. Just don't blow your ass up using it. :twisted: :twisted: :twisted: :twisted:
brian Casey
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Fri Sep 15, 2006 3:32 pm

what is the kind of ignitio that you have i there?? i cant see anything
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spudbud101
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Tue Jun 19, 2007 8:39 pm

There is a video on Youtube where stupid kids build a combustion cannon and use their dad's acetylene as fuel. It didn't explode, however, and it was amazing.
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Flying_Salt
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Tue Jun 19, 2007 9:36 pm

Spudbud, this is your fisr post so I'll just tell you instead of yelling at you that kicking up dead topics is greatly frowned upon and results in Pimpmann hunting you down and stapling you by your ears to the ceiling as he whips you with a acetylene torch.

Have a nicy day and welcome to spudfiles :)
sgort87 wrote: I hereby present Flying_Salt with The one and only <a href="http://www.geocities.com/sgort87/ghetto">Ghetto Award!</a>
SPUDMASTER91
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Tue Jun 19, 2007 10:31 pm

that shur is a purty cannon :)
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ammosmoke
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Wed Jun 20, 2007 12:45 am

Dude, err, spudmaster? Didn't flying salt just say not to post here?
ondskehem
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Wed Jun 20, 2007 1:07 am

less IS more! clean design.
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