Why not to use acetylene as spud gun fuel.

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.
Blackspire
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Sun Oct 15, 2006 4:48 pm

reaper613 wrote:has everyone just chickened out and called it quits on building bigger and better cannons, is there no one out there who will challange my oxy-ace gun with one of their own. enough with all the "dont use acetylene topics" man up and build somthing far batter than these hairspray cannons
I'm building a metal potato gun, which will be fueled by oxy-acetylene in the very near future. The chamber is going to be 2 feet long, by 4 inches, and the barrel is going to be 4 feet long by 2 inches(oh, and the chamber wall thickness is 1/4 inch, and the barrel wall thickness is 1/8 inch). Once I get all the parts, I'll post some pictures and you guys can place bets on what's going to happen the first time I shoot it :shock: .
reaper613
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Mon Oct 16, 2006 12:11 am

finally a challanger. same dimensions as my gun but with a 1inch larger chamber, guess my next gun will have to be 6 inch. looking forward to seeing what you come up with, dont keep us waiting too long
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rna_duelers
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Mon Oct 16, 2006 6:19 am

Wait for my gun..Hehehehe,well when i get the $$ to support the build.
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Metal_Soldier
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Mon Oct 16, 2006 7:18 pm

I loaded up the 'ol 3" wye cannon (Sch 40 3" wye) with a spud and the cutting torch (Oxy-Acetylene)

Best shot I ever got out of it! Left a big cake of black ash in the back of the chamber (think I had her a little rich)

Btw I know a guy that was trying the 'ol Fill-A-Garbage-Bag-Up-Off-The-Torch trick and as he was holding it between his legs static from his own body set the thing off.. Lets just say he is fortunate to still have his hearing and well I know his son so he's no worse for wear.
flash8318
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Mon Oct 16, 2006 8:15 pm

I have done oxygen and propane, Whit the small welding kit you get in home depot. I pluged the barrel with a piece of fiberglass insulation. I filled the chamber with the mixture of oxygen and propane and hit the ignitor. All I rember was knealing down and hitting the ignitor and when It blew Up I was standing up. It was in the winter in NH and I also got the pleasure of replacing my brothers vinyl sidding in the spring . Other than the barrel all that was left of the chamber was a hundred pieces the size of marbles.
Blackspire
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Tue Oct 17, 2006 12:16 am

Metal_Soldier wrote:Btw I know a guy that was trying the 'ol Fill-A-Garbage-Bag-Up-Off-The-Torch trick and as he was holding it between his legs static from his own body set the thing off.. Lets just say he is fortunate to still have his hearing and well I know his son so he's no worse for wear.
Uhh, I'd say he's probably lucky to have a few other things, seeing that the bag was between his legs and all.
Tshylea
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Wed Oct 18, 2006 9:29 pm

Acetylene by itself (like seen in the first video) is not nearly as dangerous as a 50-50 mix with oxygen. If there had been oxygen in that bag, if any of the guys standing around had not had their ears plugged, they would have serious, permanent hearing damage, and would probably have been hit buy fragments of the wood in the fire. In my high school welding class, my teacher filled a balloon about the size of my fist with oxygen and acetylene and set it off outside. He said that the first year he did that test, he used a balloon about the size of his head, and did it in a classroom (large enough for 40 students and with a 12 foot roof) and he put cracks in every window.
crsaz
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Sun Dec 31, 2006 5:23 am

the bag is not filled with just acetylene its oxy-acetylene and it's not a 50/50 mix there is much more acetylene than there is oxygen i'd say more like 75/25 or 85/15 acetylene/oxygen. fill a balloon with just acetylene and touche a match to it(not with your hand) it will make a fireball just like propane balloons but with a huge mount of soot.
newkidspudster
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Mon Jan 01, 2007 4:56 am

dang that makes me just wanna fill my chamber up with the stuff. {sarcasm}
Obctg
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Sat Jan 06, 2007 10:17 pm

i think the reason why acetelyne is feared is because of its detonation speed and temperature. not to mention is unstableness. My dad is a welder and he said he would never dream of using oxy-actetylene in a PVC or ABS gun. he said he would only do it wiht like 3/8" steel
pyrogeek
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Sat Jan 06, 2007 10:41 pm

In larger quantities or under higher pressure, acetylene can detonate. Remember, the flame front has to propogate faster than the speed of sound for it to be detonation.
Scotty
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Thu Jan 11, 2007 8:08 am

Jo I'm gunna use acetelyne with no oxy, I know ill be fine 8)
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joannaardway
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Thu Jan 11, 2007 10:24 am

I doubt it. It can easily mess you up either way.
Novacastrian: How about use whatever the heck you can get your hands on?
frankrede: Well then I guess it won't matter when you decide to drink bleach because your out of kool-aid.
...I'm sorry, but that made my year.
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Legendpilot
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Fri Jan 12, 2007 7:30 pm

You definitely have to weigh your options. Is life, let alone limb, worth more power? If so, by all means experiment and we'll all learn from it. Acetylene=trouble, period. -Lp
jer686
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Wed Mar 14, 2007 9:54 pm

ok, im a welder and i'll tell you the best fuel for a spud gun is oxy-acetylene but it has to be mixed right!!!!!! heres how: light the torch get a good neutral flame then tap it out and fill your gun. but build your gun out sch. 40 steel!!!!! or better yet sch. 80 aluminum like I did its light and strong. 1 foot chamber (sch. 80 aluminum) 6 inch, and 4 foot barrel 2inch. and some 1in handles. small and light but if you'v got oyur mixture right and point it at the moon and shoot you'll be the 2nd guy to put a potato on the moon!!!!! hahaha
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