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Went to an outdoor haunt last weekend and they had a site that utilized flames and fire.

They shot flames into the air a good 10-15 feet, perhaps more on demand. In other words, bursts of flame, much like a Hot Air balloon burner kicks out flames.

I was able to see the equipment up close and it appeared to me, they simply had two 1/2" pipes connected to "T" fitting and a large LP tank. Actually, a hose went from the LP tank, into a "T" fitting and from there, split into to pipes that were about 3 inches apart and about 48 inches high. So it basically formed a tight "U" with the LP hose feeding a "T" at the bottom. They lit the flames with another torch of some sort.

Has anyone ever messed around with anything like this? I'm wondering if there is any info on how to do this. I've seen it done on some other haunt videos, flames shooting out of dragons or even from the chimney of an outhouse. But I'm not sure how to do it.

I'm keenly aware of the safety factor....and that's why I haven't "tried" anything myself. I'm just fishing for ideas.

Thanks in advance.
 

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I would not mess around trying to build one of these, but what you describe sounds like a "weed burner." You can pick these up fairly inexpensively at garden centers.

You can get handheld units that use the small propane cylinders for character mobility. Obviously, you need to be careful when using open flames, but you knew that already. If you hold the flame nozzle upward and cover the venturi intakes, the flame will yellow and surge upward. Do not do this for prolonged periods though, it is fine for quick bursts.

Eric
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I'd also check with your local town/county/state and see what, if any, permits you might need to use this in a public setting, and also call your homeowners insurance carrier and see how much your rates will go up in the unexpected happens.
 

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I'd be interested Texan78, if you have any information.

I have a fair amount of experience with plumbing and plumbing gas line. I used to do it for a living. But my experience is with residential and commercial business installation. Not creating SFX.

So I need a little guidance if it's something I would consider attempting.
 

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A fellow haunter here in PA uses a propane cannon. I believe you can buy them as they are an actual theatrical type prop. He did not make his, it was professionally made. makes a decent sized fireball as you are describing.

Personally, the thought of using anything with a real flames in or around my haunt kind of scares me. Esp. paired up to a propane tank. about 4 or 5 years ago I had a tot fall onto a pumpkin that had a real candle in it. Was no big deal and nothing happened, but that did it for me.... I haven't even used a real candle since.....:rolleyes:
 

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BallstonManor - I appreciate your concern and understand what you are saying. My haunt is in the woods. The only thing that might burn is a few leaves (barring some type of explosion). The flames would be a large distance from spectators.

I want to restate, that I am keenly aware of the safety factor of an SFX such as this. Just as I am keenly aware of the risks of pneumatics using door closures and tire pumps.

I've seen it done, so it must be possible. And must be able to be executed safely.
 

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Just as I am keenly aware of the risks of pneumatics using door closures and tire pumps.
Ok now you've got me curious. Why'd you have to go and say something like that? Now I have to figure out what it is that can be done! LOL
 

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Ok now you've got me curious. Why'd you have to go and say something like that? Now I have to figure out what it is that can be done! LOL
Using too high a pressure blows them right up. Spectacularly and dangerously!
 

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Told ya Mark had found some of these...LoL

Don't worry Mark, we can bunk up at the local homeless shelter when we burn our houses down and plan for 2010 together...LoL

I don't see LP lines. I wonder if these are powered off of a 12 oz bottle that is housed in the base? I couldn't find any info on how they are powered.

Those things are damn loud to and would be pretty damn scary to hear go off. I am trying to figure out how to add them in. They would look cool on top of cemetery columns. I have to build new ones next season. So I might build them tall enough and mount them inside the top of the columns. I think it is funny in the video the test was done indoors...LoL
 

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If you have a compressor, you could use compressed air and a simple carb design. I would shy away from propane myself.

Using compressed air will require some very simple fittings. You could route flexible hose to your prop. A small high pressure nozzle at the end. Like one you would use to blow off shavings on a bench. The nozzle could point into a pipe. Say 2 ". Just in front of the nozzle and in the path of the compressed air you place a tube. 1/8 " should do, but depending on the volume of air you pump, the tube will have to be sized correctly to get the optimun mixture for your flame. The tube should be cut at a 45 degree at top. The opening is facing away from the air flow. This is your simple carb. As the air flows past the tube, it creates a vacuum. This will draw your fuel up from the supply tank and out to be dispersed into the air. The tank must be fairly close. You could mount it to one side. Just make sure the fuel source is beneath the top of the tube. Again some experimenting will help here. Now all you need is an ignition source. A flame will likely get blown out. I would create a very simple car type ignition. A couple of small 6 volt battery could be wired in series to provide 12 volts. With these you can control the whole process. A solenoid could push the valve on the nozzle. At the same time the batteries could run a small gear motor with a single lobe cam. The cam with actuate a micro switch. The switch is wired normally closed to supply 12 volts to an auto coil. Now you have a spark plug wire from coil to a spark plug mounted in the two inch tube. Make sure everything is properly grounded, and you have a flame thrower. As far as fuel, You could use kerosene, which is a bit safer than gasoline.

Actually I have a perfect place on the corner of my garage to place fire breathing dragon. Too late this year, but next year Hmmm !!!

Spinman
 

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I was able to see the equipment up close and it appeared to me, they simply had two 1/2" pipes connected to "T" fitting and a large LP tank. Actually, a hose went from the LP tank, into a "T" fitting and from there, split into to pipes that were about 3 inches apart and about 48 inches high. So it basically formed a tight "U" with the LP hose feeding a "T" at the bottom. They lit the flames with another torch of some sort.
First I would not recommend trying to build something it’s not worth the danger you could put yourself and others in. I only provide this information for educational purposes.

What you described sounds like a fire cannon. The basic idea with a fire cannon is that you will release flammable gas and ignite it. Propane is typically the gas of choice. Propane in a tank is mostly liquid with vapor above it. When you open the valve, the gas vapor flows out. This vapor is what you burn. As you use this propane gas more room becomes available in the tank and more liquid propane evaporates off the top. Your tank should always be upright or else you may get propane liquid in your system and could become dangerous.

Propane comes out of the tank relatively slowly, so burning it directly out of the tank would not produce a large flame it would produce a steady-state flame (like in a BBQ). To bet a bigger blast, you need to either use a bigger tank (more surface area for evaporation) or use an accumulator. Which is a fancy word for a tank. By filling the accumulator with gaseous, pressurized propane you can then open a large valve releasing large amounts of gas making a big flame when ignited. This means you would have a valve and a pipe coming out of your accumulator. NEVER put an oxidizer (like oxygen or air) into your accumulator in any amounts. Doing so could allow a flame or spark inside or traveling down the barrel to ignite the gas inside causing it to explode (purge you accumulator of all air).

I think the Chinese units use an aerosol can filled with flammable oil. These units look promising and would be the safe way to go.
 

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It has been awhile since I worked on this but it has always been something I wanted to add. I have still been thinking of a way to improve this since I first tried it but never got back around to working on it. The first year I tried it, it was a huge hit and everyone loved it and were taking pictures. Unfortunately this was like 10 yrs ago so I don't have any pictures but I wish I did. I had this concrete Gargoyle that I made this base for that would sit perfect on the peak on the front of my house. I ran copper tubing through it to the mouth and let me tell you, that wasn't fun. The tubing ran down to a manifold but before that it had a one way valve fitting whatever you wanna call it. Then I used a hose like from a fish or turkey fryer that connected the manifold to the LP tank. Also by using this hose it allowed me to use it as a regulator since it had one built into the line. So pretty much what I had was a pilot flame when lit which I had to manually climb on the roof and light. In order to control the flame though I had to manually turn the regulator to adjust the flow. It looked cool but wasn't the exact look I was going for. It blew like maybe a 6" flame. Wasn't very practical and been trying to find a way to blow it farther and blow more so it would looked more impressive. It was still cool to those who saw it. I got the idea from this Haunted House out here that did that. I might drive out and see if they still have it and get pictures and video of theirs in action.

I think the Chinese units are more practical though and I am going to use those next year. I know when me and Mark were talking about this and he was telling me about them and the price I nearly had a heart attack because they are so affordable for this effect. I have a couple of ideas where I can safely use them, but I have a year to work on it and I might connect it to my LOR since it can run DMX.
 

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Here is a video of some units set to music. YouTube - FIREcracker Suite - Lasertainment.

Holy Crap!!! You should not have shown me that...LoL People on the Christmas forums have been trying to find a way to use fire effects in there display last year and since my Christmas display is like 100 times larger then my Halloween this is PERFECT!!! Especially sicnce I am doing the Disneys "Believe in Holiday Magic" this year. Might have to do it again next year because it is to late for this year. since the programming is done for Christmas already. But it has that song in it....
 

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I just looked at the web site with the Chinese units and they have two units. One that works with LP, and another that uses an aerosol can filled with a flammable oil.

Remember you NEVER want to mix your flammable gas with an oxidizer (air, compressed air, oxygen) untill its at the point you want it to burn. You need three things for combustion to take place a fuel, a oxidizer, and heat, better known as the fire triangle. Take anyone of those away and you have no combustion.

Stay safe.
 
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