Propane filled pneumatic + pilot flame

[PVC Arsenal 17]

My friends are trying to make a movie. Another pointless, unfunny YouTube failure. I thought maybe I could come up with some special effect just for fun.

If I filled a good size peumatic with propane and fired it with a torch flame at the end, would I get a nice fireball? Or just blow myself the f*ck up?

Thanks...

[veginator]

i have seen it done with WD40 so yea it would work

[potatoflinger]

Well, I saw a video on youtube where someone did that with WD-40 instead of propane. It worked pretty well, but you might have trouble if you use only propane for pressure, you would probably have to have a small amount of propane and a lot of compressed air.

[paaiyan]

I think it would work, I can't see why not. But I disagree with potatoflinger., using compressed air in it will make it a more efficiently burning flame, and efficiantly burning propane is not as redily visible as it would otherwise be. Just use propane, then you'll get a luminous, orange flame.

[Pete Zaria]

Nothing bad should happen; as long as there's more than about 10% propane inside the gun, it won't support combustion inside the chamber, so you should just get a nice huge fireball at the end of the barrel where the propane is meeting enough air to combust.
When the chamber is almost empty, a flame will probably flash back inside the chamber and burn the remaining propane, but as long as the valve stays open, that won't be a problem. Just make sure the valve stays open long enough for all the propane to burn.

And don't hold me responsible if something bad *does* happen

Peace,
Pete Zaria.

[potatoflinger]

I think it would work, I can't see why not. But I disagree with potatoflinger., using compressed air in it will make it a more efficiently burning flame, and efficiantly burning propane is not as redily visible as it would otherwise be. Just use propane, then you'll get a luminous, orange flame.

But it will also make it a little more dangerous (as if it wasn't already dangerous enough...).

[paaiyan]

I think it would work, I can't see why not. But I disagree with potatoflinger., using compressed air in it will make it a more efficiently burning flame, and efficiantly burning propane is not as redily visible as it would otherwise be. Just use propane, then you'll get a luminous, orange flame.

But it will also make it a little more dangerous (as if it wasn't already dangerous enough...).

I don't see how... As long as there's no idiot standing in front of it, I think it will actually be safer. The flame will be cooler.

[PVC Arsenal 17]

Nothing bad should happen; as long as there's more than about 10% propane inside the gun, it won't support combustion inside the chamber, so you should just get a nice huge fireball at the end of the barrel where the propane is meeting enough air to combust.
When the chamber is almost empty, a flame will probably flash back inside the chamber and burn the remaining propane, but as long as the valve stays open, that won't be a problem. Just make sure the valve stays open long enough for all the propane to burn.

And don't hold me responsible if something bad *does* happen

Peace,
Pete Zaria.

That shouldn't be a problem.. I'm going to use a burst disc for the added sound. Thanks.

[Pete Zaria]

Here's why it's a bad idea; you don't want a combustible mixture inside the chamber..... duh.....

Use AT LEAST 50% propane to prevent accidental ignition. You're trying to make a fireball gun, not a hybrid.

Peace,
Pete Zaria.

[potatoflinger]

I don't see how... As long as there's no idiot standing in front of it, I think it will actually be safer. The flame will be cooler.

Well, I may have been wrong about the compressed air and not the propane, because I was just thinking about some of the propane igniting while there was still some left in the gun, which would be dangerous if the valve closed while there was propane combusting (is that a word?) inside the gun. But, now that you said something about it, I think you are right.

[mtronic]

I have shot butane out of my old ball valve cannon. However I used air for the chamber and then put the butane down the barrel, it works a lot better with the ball valve because you can control the air speed.
Too fast and it wont ignite. I used 40psi and a 2 second spray and it gave a 2mtr diameter fire ball. Its fun, but be careful not to over heat the guns barrel
Hope this helps.

[MisterSteve124]

or you could just pour a little bit of gas in after the valve is closed if propane doesn't get the "look" you want.

[DYI]

I have tried exactly this with my burst disk gun, and it didn't work at all. With a ball valve gun opening somewhat slowly and an oversized chamber it may work the way you want it to, but the burst disk method won't work. It will simply blow out the pilot flame before the propane ignites.

[mark.f]

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[mtronic]

Yes he could.... but he would need to make sure the area that he will be shooting in isnt at risk of burning to the ground. Petrol will act like a flame thrower and launch burning fuel all over the ground and its hard to extinguish. I think it would be a little unsafe, but its up to him. It might make for an interesting "share you cannon accidents" post though.

ps this was at the gas post.......damn you two speedy posters
And yes I think a burst disk would be too fast, ball valve all the way