metal gun

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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super spuder
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Mon Apr 09, 2007 11:45 am

for my next project i was planing on making a highpowered metal combustion cannon. but then it occoured to me when you try to get the spark to the midle of the combustion chamber with a bolt or screw or somthing. it is going to want to jump from the bolt to the side of the cannon and i dont that is going to make a quick or verry good combustion. how do you fix this problem or is the spark jumping to the wall fine, is there some way to hook up a car spark plug? i have heard that that works good.
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FeLeX
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Mon Apr 09, 2007 11:52 am

Just screw the car sprak plug in and thats all.
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super spuder
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Mon Apr 09, 2007 12:25 pm

how would you get the spark plug to spark thou
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FeLeX
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Mon Apr 09, 2007 12:31 pm

Connect the wires to it? One goes to the tip and the other goes to the chamber (if it metal). I can draw you a diagram if you want to.
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super spuder
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Mon Apr 09, 2007 12:33 pm

the wires from what thou a bbq lighter. or would it have to be something like a stun gun circuit.
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FeLeX
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Mon Apr 09, 2007 3:24 pm

Many people say that stun gun is better. I relly couldnt care less, bbq or stungun, both are fine. The main difference is the price, but if you can you should just buy a stun gun off ebay. Shouldnt be very expensive there.

About the wire connection. If your metal chamber conducts electricity you could just connect one wire to the chamber and another to the metal thingy sticking out from the spark plug. Good Luck!
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ArticWolf
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Tue Apr 10, 2007 5:16 am

I you can get or have a spark plug wire just cut off one end and tape the wire from the bbq igniter or stun gun and put the spark plug wire on the spark plug and the other wire to the cannon somewere that should work. I haven't done that yet but I am an auto mech. so I do mess around with these things. I was even going to try a ignition coil and a turn signel flasher for the same thing till I got my stun gun LOL
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chaos
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Tue Apr 10, 2007 6:07 am

hehehe yer i had this problem with mine LINK

what i did is thought..... conclusion was there BBQ peizo sparker came with a insulated probe so i just sharpened the tip, earthed the other wire to the chamber and whola! done.

piccie

Image

peace.
Matheusilla
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Tue Apr 10, 2007 9:10 am

If you want to get fancy you can get one of these "spark plug hole" repair kits. You drill a hole for the spark plug, tap it with the tap from the kit and thread in one of the bushings from the kit (you could also put some "loctite" on the bushing before you screw it in). You will have the perfect threaded hole afterwards (spark plugs have their own thread pitch system) so that you can remove the spark plug as many times as you want without damaging your gun.
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mark.f
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Tue Apr 10, 2007 9:13 am

If it's just a combustion, (not a hybrid), you can do what I did on my first small metal cannon and just drill a 1/16" hole, then run two wires through it and tape a cardboard spacer between them on the inside, then wrap on the outside with between five to ten wraps of electrical tape.
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super spuder
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Tue Apr 10, 2007 3:08 pm

thanks. that was very helpful. i duno what i am going to do yet, but you guys gave me some great ideas :P
heavymetalsarge
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Thu Apr 12, 2007 8:55 am

sounds neat, but my advice it is to use threaded connections + welding if u would like to use really powerful fuel. I am currently in the design phase of my gun that I am wishing to make out of 4" diameter high pressure steel pipe.
When it is finished I plan to make it look like a actual artillery piece one because it looks cool and two for wheeling it around
if it doesn't involve a loud bang it isn't powerful enough
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super spuder
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Thu Apr 12, 2007 3:38 pm

that sounds sweet :lol:
souljahz_unite
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Wed Apr 18, 2007 9:35 pm

just a question since i am kinda noob to this all : (just drew up combustion plans for a basic gun a week ago)

if its a metal gun... wouldnt the combustion rapidly heat the combustion chamber to be really hot? i guess on a stand it wouldnt matter, but maybe im not thinking it in the right way?

a metal combustion gun does sound like a cool idea though.
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frankrede
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Wed Apr 18, 2007 9:59 pm

short answer.........no.

long answer...........noooo.
The combustion actually only lasts a fraction of a second, not enough to heat up your chamber significantly..
Current project: Afghanistan deployment
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