Hobbies And Interests
Things You'll Need
Instructions
Take the can of food and open it using the smooth-edge opener. Empty it out into a bowl for later consumption. Clean and dry the can and lid. Cut a small hole in the lid for the flame to escape. Take a small nail and puncture some holes in the bottom of the can from the inside out (so that the inside of the can is smooth. Be careful not to get cut on the can. Make sure that the holes are in the middle of the can and not on or very near the concentric rings in the bottom of the can.
Cut a very small "fuel injection" hole using a drill into the side of the can. Put a block inside the can and clamp it down so that the can doesn't get away from you as you are drilling. Since the fuel is going to be limited to the liquid that we are providing and this version of the engine is designed to run only in short bursts of time to avoid burning itself up, this hole will be used for ignition only at this point though you can experiment later. Use a file to file down any sharp edges to avoid injury.
Cut a small piece of aluminum can that can cover the holes that you just put into the bottom of the can. Use the J-B Weld to affix it in a way that allows it to flap freely. This forms a type of valve that blocks the gas as a one-way valve so that when the gas expands in the can, it goes out the back and not the front. A partial vacuum will form after the gas cools slightly, sucking in more air from the front as needed.
Place the lid that you removed using the can opener back on the can. Tip the can on end and let it stick its exhaust up in the air. Make sure that you use the spare blocks at this point to sit under your can in a way that allows the air to enter the intake (the valve side of the can). Make sure that you affix the can to the two blocks using a screw in each block. You might do this by drilling into the sides of the can at the extreme front of the can and predrilling a hole into the blocks of wood where you want the screws to go in. The holes in the wood and can need to be the right size so that there is no leaking from the can and there is good "bite" into the wood. The difficult part comes in getting the screws into these holes and then into the blocks. If your screwdriver is short (or flexible) enough, you can potentially tighten the screws or instead opt to use needle-nosed pliers to tighten it. If you do a test run and are confident of the hole size in your lid, you can use the J-B Weld to make it permanent.
Light the engine after covering the openings to the engine and the engine is shaken to distribute the flammable liquid fuel. You will need to be careful that there is no leaking out the front. Additionally, if there is too much fuel vapor and the fuel air mixture isn't just right, the engine will be hard to start up. Shaking the can distributes the fuel which evaporates enough to supply vapor. Since you have a series of holes in the chamber, you have to be careful of any fuel that leaks out as it is a fire hazard. Use the oral syringe to draw the methanol and then gently squirt a small stream of liquid down around the inside of the can, allowing the chance for the liquid to form vapor as it runs down the insides of the can. Do not inhale the vapor; make sure that you can still keep the vapor in the can for combustion. The liquid that runs down the sides should be stopped by the concentric circles in the bottom of the can. Get your long-nosed lighter ready. The fuel injector hole is used in smaller engines mainly for ignition, rather than to inject more fuel. Light the lighter and put it up next to the hole so that the flame goes inside the can through the little hole for ignition. The engine may need a lot of fine tuning to get it working just right. You also have to use the hair dryer to force in hot air into air the intake past the valve so that the engine gets enough air into the fuel air mixture to run. Remember that this engine is only supposed to run for shot periods of time to avoid overheating of the parts but this should be enough to get you started. Be safe and always work under the supervision of an expert. Better yet, have an expert do this for you so that you don't get hurt.
The original type of pulse jet consists of a metal tube that can withstand the heat of operation. It has two intake "holes" at the front. One is for usually fuel injection where the fuel is 'injected" but we will use this to light the engine instead. The other intake hole is much larger and is used to draw in air. The small holes you have put in the bottom of the can are the air intake holes, even though we will refer to it as the air intake hole. A second hole will be referred to as the fuel injection hole even though it is really used to ignite the engine. The fuel injection hole must be cut into the side and be made small (diameter of a small nail).