The Backyard Flamethrower




Posted in WorkshopTools

Introduction: The Backyard Flamethrower

This is an easy, cheap flamethrower that I created so that you can create your own flamethrower. This flamethrower could and should be used as a tool for brush clearing, which is what many firefighters use flamethrowers for. For this flamethrower to work, you must start the lighter first, then pull the Caulking gun trigger. The flame will shoot out 3-5 feet from the gun, and is very hot. That being said, YOU CAN BURN YOURSELF WITH THIS FLAMETHROWER!!!

Step 1: Step 1: Materials and Tools


Caulking Gun-Home Depot

Butane-Home Depot

Butane Twist Lighter-Home Depot

Small piece of scrap plywood or bottle cap

Hose Clamp 1/2" Band, 3" to 5" DIA-Home Depot

PVC Pipe 3" x 2' (optional)-Home Depot

Vinyl Sticker (optional)

Spray Paint (Optional)

Tools you will need:

Band Saw

Drill Press

1/8" Drill Bit

High Temp Hot Glue Gun


Pliers x2

Measuring tape

Chop Saw (optional)

Vinyl Cutter (Optional)

Step 2: Step 2: Preparing the Caulking Gun

This Step is very important as, if you skip this step, your flamethrower will spew uncontrollably after you lift your finger off the trigger! This actually happened to me, and the way I learned to stop it was by sliding the bar off of the canister and blowing out the small flame from the depressor, as the depressor also caught on fire. You will use the two pliers to unscrew the top screw, pictured here, and taking off the wire spring from the left side (the side not enclosed). This makes it so that the bar stays in place and doesn't move forward.

Step 3: Step 3: the Butane Depressor

Now you will need to cut that scrap wood with a circumference the size of a bottle cap, as pictured above. You could use the bottle cap, but is has a tendency to melt when heated too much, which is what happened to me, and is why i know use wood as the depressor. When cut to that size, find the exact middle of the wood and use he 1/8" drill bit on the drill press to drill a hole in it. this will be stuck to the end of the butane canister in order to depress the end and spray the butane, as seen above.

Step 4: Step 4: Cutting Your PVC, Painting It, and Attaching It (Optional)

Put your butane canister with the depressor of your choosing into your caulking gun, push the bar until the end of the depressor is right up against the end of the gun, and stop. If you were to pull the trigger, butane would now spew out. Set your caulking gun down, measure how long the bottom of the butane canister forward to the end of the caulking gun, keep that measurement and measure it out on your PVC pipe. Mark it and cut it on the chop saw at that length. Next, if you want a design, create a sticker on Inkscape, upload it, and cut out a sticker using a vinyl cutter, attach it to the PVC pipe, and spray paint the pipe. Wait for it to dry and lift up the sticker and your design will be there. Then you can use the high temperature hot glue gun to attach it straight to the butane canister. The reason for this being that if you attach it to the caulking gun, you could not replace the butane.

Step 5: Step 5: Attaching Your Lighter

Put the Hose clamp around either the PVC pipe casing or the butane canister, put the lighter you are using through the clamp, and tighten it up with the flathead screwdriver until the lighter fits snugly. When finished, you have completed your flamethrower. To fire it, light up the lighter and depress the trigger and a 5 ft flame will shoot out. THIS IS DANGEROUS AND WILL BURN YOU, YOUR FRIENDS, OR YOUR HOUSE DOWN!!!

Step 6: Step 6: Future Plans

As far as future plans go, I would hope to learn a way to keep the pilot light (lighter) lit without me having to hold it down. After learning how to do that, i would add a handle to hold on to with my left hand and keep it steady. Other future ideas include turning the bar sticking out the back into a shoulder rest, adding a heat shield to the gun, and figuring out how to incorporate a mini tank of water to the side of the gun in case a fire gets out of control.



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    That works well! I like the paint job :)