Here's How to Make Your Own DIY Flamethrower From Scrap

With that done, begin to cut any other lengths of pipe you may or may not need for the device. This is most easily achieved using an angle grinder, but you can do the same with a hack saw or similar. 

Where needed, you can also cut threads on any pipe ends that need them using a ratchet threader. 

Keep cutting and shaping your old pipework as needed until you have all the bits that you need. 

Step 2: Weld the pipes together

With all the lengths of pipework needed, you can now begin the basic assembly of the flamethrower. Take your welding torch, and weld the lengths of pipes together as needed. 

Where needed, weld washers and steel rods to the pipework to make things like the handle, etc. Drill holes through the lengths of pipe, where needed, too. 

Continue to weld and thread pipework as you go to complete the main assembly. Unless you have parts like tube connectors handy (for the gas pipes) you may need to machine those parts.

With that done, connect rubber tubing to the setup as required. 

Step 3: Prepare the gas cylinders

Next, take your fire extinguishers and completely empty them. You can decide if you want to make a game at this stage or not. 

Once empty, carefully dismantle the fire extinguisher by removing its top. You can use a vice to help you out here. 

Once done, clean out any residual contents of the fire extinguisher as best you can. Once done, give the inside of each a good clean. 

With that done, weld some threaded pipe connectors to the top of each extinguisher bottle. 

If needed, you can also cut down the extinguisher bottle to make them smaller by trimming off the bottom and cutting the main body down to size before welding the base back into place. 

Where needed, drill holes through the bottles and thread rubber tubing into place. Once complete, you can then paint the bottles to the desired color. 

Step 4: Complete the flamethrower

With all the bits now complete, we can complete the final assembly. Tape or strap the old fire extinguishers into place on the main body of the flamethrower as needed. 

Connect up all the rubber tubing as well at this point. For the trigger, wire up the old brake handle and brake cable to the assembly so that it can be used to open the valves on the fuel canisters as shown in the video. 

Attach the trigger to the main foregrip of the flamethrower too. Next, add the main flamethrower barrels to the assembly. 

Next, make and connect the nozzles for the barrels, and add some heat insulation as needed in places. Also, add a piece of old cloth to the end of the lower barrel to act as the ignition source. 

Fill the main fuel canister with dextrin and seal it, then connect to the flamethrower. Next, soak the old cloth in liquid fuel, ignite, and then take your flamethrower for a test run!

Obviously ensure this is in a safe, open space!

If you enjoyed this tutorial, you might enjoy making some other DIY weapons? How about, for example, your own 40K-inspired chain sword?