Monsters of the Potato Gun World (video update 2/3/08)

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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DYI
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Sun Jan 20, 2008 6:58 pm

We don't have arguments around here, we dicuss
Exactly. And safety is always good, however alarmism isn't. This isn't any less safe than using propane as a fuel, just less convenient.

@Pizlo: You are correct. Unless a detonation occurs, the chamber generally won't explode with a liqht projectile. For heavier projectiles, the acceleration is slow enough that significant pressure build up can occur. However, the maximum combustion pressure of most gaseous fuels isn't very worrisome to a pressure rated chamber.

Using gasoline in a carboard chamber could very well result in the whole thing burning up when you vent the chamber, but it isn't going to damage you very much (unless you set yourself on fire of course :roll: )
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Sun Jan 20, 2008 7:06 pm

DYI wrote:
We don't have arguments around here, we dicuss
Exactly. And safety is always good, however alarmism isn't. This isn't any less safe than using propane as a fuel, just less convenient.

@Pizlo: You are correct. Unless a detonation occurs, the chamber generally won't explode with a liqht projectile. For heavier projectiles, the acceleration is slow enough that significant pressure build up can occur. However, the maximum combustion pressure of most gaseous fuels isn't very worrisome to a pressure rated chamber.

Using gasoline in a carboard chamber could very well result in the whole thing burning up when you vent the chamber, but it isn't going to damage you very much (unless you set yourself on fire of course :roll: )
Shhhhhhhhhh! Salty mite be listening, worse yet, Benstern!
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DYI
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Sun Jan 20, 2008 7:09 pm

Shhhhhhhhhh! Salty mite be listening, worse yet, Benstern!
:? I assume I haven't been here long enough to get that one.
And those are some awesome smilies 8)
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Sun Jan 20, 2008 7:17 pm

Salty is the forum pyro, and Benstern is (from what i've read), is the words most dangerous spudder!

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See what I mean, thats him with the arrow!
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rcman50166
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Sun Jan 20, 2008 8:31 pm

I think I would get along with the two characters mentioned. I like dangerous things. My other hobbies are airsoft, paintball, high power amateur rocketry, tesla coiling and other high voltage electronics, projectile design and electro mechanical acceleration systems. (ion engines, coil guns, rail guns, electroplasmadynamic accelerators, and linear ion particle accelerators.) I may be a newb here but not in my other domains! Here's a link to prove it.
http://www.ctsciencefair.org/year/docum ... hurs07.pdf
My Name is Thomas Ford. Look for it on the site.
Last edited by rcman50166 on Sun Jan 20, 2008 8:37 pm, edited 2 times in total.
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DYI
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Sun Jan 20, 2008 8:36 pm

Isn't Benstern who disperses the random "D0NT USe ABS YULL BL0W UP!!!11!one" type messages? From what I've seen, he's the best example of overzealous safety and consistently inaccurate information on the forum.

Salty hasn't posted much lately, has he?

And RCman, those are some interesting hobbies. I'd be into all of them if I didn't have to work for my money...
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rcman50166
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Sun Jan 20, 2008 8:38 pm

DYI wrote:Isn't Benstern who disperses the random "D0NT USe ABS YULL BL0W UP!!!11!one" type messages? From what I've seen, he's the best example of overzealous safety and consistently inaccurate information on the forum.

Salty hasn't posted much lately, has he?

And RCman, those are some interesting hobbies. I'd be into all of them if I didn't have to work for my money...
lol that is so true. All of my hobbies are supported by my job at a movie theater. I just find ways to be ultra cost efficient.
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DYI
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Sun Jan 20, 2008 8:48 pm

Between sports, other hobbies, and my girlfriend, not a whole lot of money seaps through the cracks. Spudding gets rather impressive results for relatively low costs. For only $500 or so, I built something that can shoot anything solid with a decent weight through indeterminate amounts of plywood and sheet metal, and still go right through a building, which can't really be done with railguns (although their energy potential is much higher).
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rcman50166
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Sun Jan 20, 2008 9:00 pm

DYI wrote:Between sports, other hobbies, and my girlfriend, not a whole lot of money seaps through the cracks. Spudding gets rather impressive results for relatively low costs. For only $500 or so, I built something that can shoot anything solid with a decent weight through indeterminate amounts of plywood and sheet metal, and still go right through a building, which can't really be done with railguns (although their energy potential is much higher).
hmm... none of my projects in any of the domains that I mentioned ever break $200. With $500 I could build a coil gun that feeds a rail gun that initiates an electroplasmadynamic thruster, which starting that kind of engine has been compared to lighting a match in a hurricane because the unnecessary sources of energy required. I squeeze every penny.
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oXo Swivel oXo
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Mon Jan 21, 2008 12:30 am

Wow what an awesome gun. its so cool its hurting my computer with its aura of coolness...

...noone knows who this is...
AWESOME



({[Tom i need tyler's game back cuz i think i'm going to his house tomorrow or at least soon.]})

by the way that last post was waaaaay o confusing... maybe im just too tired
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SpudFarm
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Mon Jan 21, 2008 5:49 am

whoa oXo your a strange person :shock:
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rcman50166
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Mon Jan 21, 2008 8:51 am

lol Damon email me in the future. This site is for the spud cannons.
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Mon Jan 21, 2008 10:43 am

Good job with the duct tape dude, Larger dia. chambers make me nervous, because the larger the dia, the lower the pressure rating.You oughtta be allright though cause although I don't have any data to back this up, my own trial and error experiments lead me to believe that spray'n prays (no burst disc) never develop more than 100psi at any point. (As long as you stick to taters'n such, and you don't chamfer out the inside of your barrel knife to much.) I did have a metered propane Sch 40 3' chamber blow on me once. It just cracked and didn't shatter (Lucky Me)That chamber was almost two years old.and had fired hundreds of shots so... heres the the best advice I could give out... Regardless of how much you like any given cannon, If it's plastic, and you shoot it a lot, sooner or later it's gonna wear out, with potentialy dangerous consequences. throw it out, save the expensive parts (sparkers,meters,regulators, valves,rifled barrels, etc.) and build another one. isn't building and testing new ones most of the fun anyway?
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pizlo
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Mon Jan 21, 2008 11:11 am

I can handle burning cardboard, but I cant handle pvc shrapnel. I can handle 2nd degree burns, but I think Pvc shrap to the face would be quite different.
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rcman50166
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Wed Jan 23, 2008 7:54 pm

So speaking of gasoline powered cannons, does any one think it would be possible to use a pump action (barrel attached to a piston inserted into chamber) coupled with a carburetor to create a combustion similar to how an internal combustion engine works? I've fumbled with the idea (which is how i came upon gasoline as a fuel) and i think it may be feasible. The best setup would be straight tube design and the only problem would be the consistency of the caburetor.
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