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!!!
Nitrile gloves (preferably thicker/better chemical resistance than I used) -Drug store-
Denatured Alcohol -hardware store/department store-
Pure SrCl2 hexahydrate salt -eBay/chemical suppliers/United Nuclear-
Boric Acid -Hot Shot Roach killer (check the ingredients) -hardware store-
Copper(I) Acetate and/or Copper(II) Acetate -eBay/ chemical suppliers/United Nuclear-
Potassium Chloride (No Salt Salt- or get the pure stuff) -grocery store/ebay-
Sodium Chloride (regular table salt)
Bernzomatic mini butane refill canisters (There are other similar products out there, but their dimensions may be different and I don't know how well they will work for this) -hardware store or Home Depot found with in area w/ barbeque lighters-
Leather strips or a leather belt to cut up (fuel tank strap)
Adhesive hook and loop velcro strips -hardware/walmart-
Tiny bic lighter (optional)
All metal lipstick tube (small retractable metal makeup brush w/ cap could work too) -eBay/department store/metal lipstick pipe on amazon may work as well-
4 tiny machine screws with nuts (many workable sizes)
4 slightly larger machine screws with nuts (also many workable sizes)
1 small machine screw with locking nut (pick a small size)
Aluminum sheet .064" thick -Ace Hardware/eBay-
Aluminum sheet .032" (optional) -Ace Hardware/eBay-
Rectangular brass tube (optional) -Ace Hardware-
Flat fiberglass wick/fire stove component -Ace Hardware-
-2.3 mm - 2mm inner diameter (Must be this diameter for safety) nitro line silicone tubing (I used DU-BRO 2239) -RC hobby shop/Amazon/eBay-
2 small flat washers(many workable sizes, but must be able to push down butane tank nozzle) -hardware store-
Large butane refill canister with standard refill nozzle -hardware store/walmart-
Cups, HDPE plastic containers, or glassware to mix up and measure colorant solutions
Stir rods or sticks
3/4" x 5/8" brass hinges -Ace-
Lexan polycarbonate sheet .1" aka 2.5mm thick (plexiglass is too weak and will break) -Home Depot-
Brass rectangular tube 8mm x 4mm -Ace hardware- (optional)
Thread -Walmart/Michael's- (optional)
3/32" x .014" round brass tube -Ace Hardware-
9" long reusable zip tieabout 1/4" wide -Walmart-
High temperature silicone muffler paint -auto stores-(optional)
Big ole walking stick (preferably enchanted) -Local walking stick emporium-
Not everything is pictured.
Rotary tool with fiber reinforced metal cutting wheel (use safety glasses while operating especially with cutting disks)
Band saw (optional)
Metal cutting hack saw (optional)
Needle nose pliers (preferably wide and flat)
Clothing that does not contain: polyester, nylon, spandex, or any other material that could melt to your skin if caught on fire
Large damp cotton towel (for fire safety)
Bucket of water
Syringe w/ no needle (hardware store/local crack dealer)
Metal vice (optional, but highly suggested)
Leather sewing needle (Walmart/Michael's)