In case no one told you, flamethrowers are really dangerous. This is NOT an instructable for kids! This is for educational purposes and if you attempt this you are doing so at your own risk. I am not responsible if you get hurt attempting this. The responsibility for your safety depends on you! I try to discuss how to do this safely throughout the instructable so, READ EVERYTHING CAREFULLY, but realize I can't think of every safety problem. HAVE A FIRE EXTINGUISHER HANDY! If you do not have a high level of understanding of the chemistry and physics involved you really should not do this.
That said, science and learning without danger would yield no cars, no fireworks, and no disease cures. So, I'm going to donate my body to some dangerous science!
Maybe some of you experienced a common flame test lab in high school. The one where you try to identify the presence of different metals by dipping little sticks in alcohol mixed with salts and observing what color the solution burns. This is basically like that on super soldier serum. This little baby can shoot up to 5 feet of flame and shoot two colors at once (three colors are possible if blending the fire streams). This thing can produce impressive flames for up to twenty seconds. To me, that's pretty sweet for a pocket-sized flamethrower holding maybe 20 grams of fuel.
BUT CAN'T THE FLAME GET SUCKED INTO THE CANISTER AND BLOW UP?!
No. In this case the fuel canister is made safe with self pressurizing butane fuel. In order to have fire you need fuel and an oxidizing agent such as O2 (makes up ~20% of air) or N2O(nitrous oxide) or one of many other oxidizing agents (oxygen may not even be involved). Since the canister is full of fuel with no oxidizer, it is not going to explode. If this were not the case, bic and other butane lighters would all be potential grenades in your hands. Their fuel sprays directly from where it is stored, into the flame. Some may say, but I've seen videos of lighters turned into little explosives. True and this could blast fire everywhere too if the plastic canisters melt and release the fuel. The container can explode if there is a second hole in the container, as this could cause air to get sucked up into it. You still have to be careful here.
To achieve colored fires another fuel, 100% denatured alcohol, is added to various fire coloring ionic compounds and mixed in with the butane. Some of these ionic compounds are toxic (very small amounts are used though), as is denatured alcohol. Yet another reason to be cautious.
Why do the chemicals used produce color? As the metals in the ionic compounds get hot, their electrons get bumped up to a more excited orbital state. It is an electron's nature to not want to stay in this excited state. So, to go back to the way it was, it rids itself of energy in the form of light. Due to different metals having electrons in different orbital states, the different metal's electrons emit different colors of light when excited. Since the alcohol and butane don't really emit much visible light, when burned efficiently, (like with the high pressure nozzle used here that mixes in a lot of oxygen with the fuel ) you see the colors emitted by the metals clearly.
How does it fire? I just simply push the little clear plastic tabs down onto the butane tanks' valves and out comes the pressurized fuel over a flaming pilot light wick. Each tab activates one tank making multiple colored blasts possible.
Make sure to read all the picture notes too.
You can't be a convincing pyromancer/pyrokinetic without fire! Turn an ordinary walking stick into a WIZARD STICK OF DOOM!!!