Flamethrower help.

[mik3v]

okay so my friend and I are creating a flamethrower.
We have seen people use an oval looking pvc fuel tank. But we want to use gasoline as the main fuel and we've hear that gasoline corrodes pvc pipe. Therefore, does anyone know how else we could make the fuel tank. We are going to pressurize the tank with either propane or with an air compressor. Preferably the air compressor.
Help? comments? critique?

[Ragnarok]

Well, I've got something else to go and do now, so I can't spare much time for a fuller post, but the gasoline thing is actually a myth. There's a test from the old Spudtech forum archive that's well worth a read:

http://www.spudfiles.com/spudtech_archi ... f=6&t=7896

[mark.f]

Well, this is kind of a grey area for the forums, but I will tell you NOT to pressurize your tank with compressed air. Use an inert gas.

[john bunsenburner]

Best flame thrower is a water gun, gasoline and a lighter up front
Keep it simple stupid(kiss)...

[MountainousDew]

Best flame thrower is a water gun, gasoline and a lighter up front
Keep it simple stupid(kiss)...

Nah, I had a water shotgun that shot water, well, like a shotgun. I filled it with lighter fluid and put a pilot light in the front, and it shot big fireballs the size of your fist, with some good distance too!
I think I got almost 30 feet with it...

[mark.f]

Guys, those are like BIC lighters compared to what OP is trying to build.

[mik3v]

Guys, those are like BIC lighters compared to what OP is trying to build.

haha yes they are. So, I am leaning towards doing gasoline in a pvc fuel tank pressured with propane. sound good? i would really like to just pressure it with air though because we have an air compressor and its cheaper... whats wrong with that?

[rp181]

the oxygen in the air pressurized, with gasoline fumes, could cause a explosion. Propane is fine, just make sure you purge the entire chamber with propane first, no oxygen should be present ANYWHERE.

[ramses]

I doubt the oxygen would be a problem as long as a good portion of the gas was propane or inert. I don't think purging the tank with propane would be necessary, as long as the mix is too rich to ignite (>9.8% propane?) I would add a margin of safety to that because of incomplete mixing, but >20% propane should be plenty.

[Sticky_Tape]

Um I'm not sure guys but I think gasoline and compressed air in a tank wouldn't cause an exsplosion simple because of the exstremely rich mix.
Sorta like a hybrid cannon that has too much propane fuel in it. I think your biggest concern is how gasoline supposedly corrodes pvc.
EDIT: beaten?

[brogdenlaxmiddie]

Am I the only one who thinks pressurizing gasoline in any form is a bad idea??

[Technician1002]

Isn't this topic forbidden by the rules.. Flaming projectiles etc.. I'm flabbergasted the thread is not locked yet.

[rp181]

Ya, it is against the rules. But if someones going to do it, may as well do it safely....

[KineticAmbitions]

Am I the only one who thinks pressurizing gasoline in any form is a bad idea??

Yes, you are.

Besides, what's wrong with pressurising gasoline anyway? It's not unstable, and it isn't hypergolic with anything you'd expect to find in the average PVC pipe (or most other pipes, for that matter). It also isn't a severe health risk if it does leak out. In fact, the only real problem with gasoline in a flame thrower is the low viscosity of the fluid, meaning that the stream can lose its cohesion completely before it reaches the target.

Now, if he were to use hydrazine...


And as to being against rules: he's not discussing launching an incendiary projectile or explosive device from a spudgun, or using solid propellants, and this is in the Non-Spudgun related discussion forum.

[mark.f]

Hence the "grey area". I've seen topics on flamethrowers locked and deleted before.

And your average car engine pressurizes gasoline quite a bit every day (at least fuel injected models).