Hydrogen Powered Nerf Gun
I wanted to expand my knowledge into engineering, so I started researching things that interested such as how thrust is created in engines, how a cathode ray tube worked, and how speakers create sound. How Ion thrusters work puts me in awe. As a kid growing up watching youtubers such as the Backyard Scientist and the King of Random, I remembered some crazy projects they did using hydrogen. The craziest thing I could think of the make was a hydrogen powered nerf gun. After some minimal research on YouTube I found out it had already been done. But that didn't stop me, I wanted to make one that was better and more powerful.
Bubbler
Generator Chamber
Since I wanted to increase the output speed of the generator, I applied Bernoulli's Principle which states a fluid's speed will increase with the decrease of static pressure. In other words, if I create a small exit hole for the gas to escape when the pressure increases, the speed of its output will increase. For this concept I place a small male pipe connector in the top of the screw cap so I could connect a polyethylene tube. I created an airtight seal using the gorilla silicon glue and used thread seal tape to wrap around the threads of the cap to create a seal that I could unscrew when necessary. My first generator design was based off a video I had found on Youtube utilizing 8 bolts, 2 washers, and 2 plastic washers. Since I could not locate plastic washer's in store, I used 2 neoprene Washers.
Originally, to hold the generator together I used the same silicon glue I had previously used to create airtight seals on both chambers. I did not realize at the time that silicon glue does not stick to metal well. After the glue I had cured it somehow held the generator together. My next step was to test it. I had placed it in a pitcher full of water mixed with the electrolyte since the glue on the generator chamber was still curing. I connected a 9v battery and the generator work perfectly. But since the glue was not designed to stick to metal much less hold a hydrogen generator together, the glue had almost entirely dissolved during the electrolysis process. I could not find a new solution to holding the generator together, it was so flimsy I needed a quick drying adhesive. So I changed my approach.
My first goal for this project was to make a small, cost efficient, and still powerful hydrogen generator I could mount on the nerf gun. After watching some videos over hydrogen generators, most would use clear acrylic tubes that way you could see inside the generator. Having no tool necessary to cut acrylic I settled for some simple PVC pipe I had found at Home Depot that was wasn't too wide to mount on a nerf gun, but long enough to cut in half to create both a bubble and the generator. Thanks to the kindness of my carpenter friend, he allowed me to use his band saw to cut the PVC in half to create the bubble and generator chambers. Knowing that hot glue doesn't stick very well to PVC because of the wax coating, I bought some silicon gorilla glue designed for waterproof sealing to seal the base cap and screw top.
First Generator Design
PVC Screw cap with Thread tape
The generator worked by applying voltage to the washers by using a round wire connector terminal. Those wires would be connected to 2 bolts inside the screw cap that way an external battery could be connected. The top washer would be connected to the positive terminal and the bottom washer to the negative terminal. The actual bolts would be fed through 4 holes I drilled into the washers. To prevent a connection between the washers I used the neoprene washers as insulators. The bolts would be laid side by side placed in a positive-then-negative fashion. It will be place into the generator chamber full of water mixed with potassium hydroxide (an electrolyte) to make the water more conductive. When voltage is applied, the hydrogen in the water will be split off from oxygen through a process called electrolysis.
Screw Cap Bolt
