This was labeled Hydrogen/Oxygen combustion cannon. The car starting in the background cylinders was used for ignition.

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Now that I remember it (well; it didn't happen to me but to someone I know) My friend's dad, Roy Coon, had made a simple pnumatic using ABS pipe fittings :wink: and a 1 and 1/2" PVC ball valve for fireing held together with some special glue he had. Surprisingly, even though ABS is not pressure rate...

^Accidential Discharges :roll: My accidents involved me trying out my ignitor by dry-fireing (fuel but no projectile) On one shot; I had put too much butane in the chamber so it flooded and resulted in no ignition. I later decided to see if the spark plug was working by removing the end cap and look...

Back when I was a freshman in High School; one of my friends,Tony Ghattes, was messing around in our KMart and he got on the loudspeaker and yelled "Customer Service to the fitting rooms, please!" in a high pitched voice. All he got from a store employee who was passing by was "Are you causing troub...

My cousin built a replica of the German cannon Big Bertha out of 4" steel pipe and calcium carbide. We had to stop using it when people a quarter mile away reported windows and plates rattling Embarassed. But yeah that was bad idea theatre....I like the idea of using pneumatics because a piston val...

I haven't been here for a while (been busy with other hobbies and schoolwork) but this was something I thought of a long time ago when I made a couple mini-launchers that fired using film containers. I started with design that was simply a combustion gun scaled down then later drew up a "pistol" ver...

Pure hydrogen actually has less energy density than the same volume of a hydrocarbon based fuel (like propane) Hydrogen is more of an energy storage than a fuel; you have to reform some other fuel or use electricity to split water. Being that I'm into alternative fuel vehicles as well, I'm learning ...

Most residential valves are rated 125 psi. Rain Bird has some that can do 150.

If you can find the heavy duty brass commercial inline valves, those can do over 200.

It will probably work better sprayed. I tryed using a liquid fuel once (denatured alcohol) and I poured it. The puddle it created stayed on fire after the shot instead of extinguishing and nearly melted the chamber.

More like these

http://www.cornerhardware.com/index.php ... _6942_7720

I converted a Nerf gun into an airsoft gun as well. I used an "Eagle Eye" and took the gun apart to get to the chamber. I then removed this little pin that blocks you from sticking stuff into the chamber and placed a small straw through the hole then taped a larger straw (from In-N-Out burger) aroun...

You could try my relay trick. Just replace T1 with the coil http://img.photobucket.com/albums/v499/yuandrew/Site/relay-coil.jpg A better way would be to build a 555 timer based pulsing circuit or a CDI circuit. http://ourworld.compuserve.com/homepages/Bill_Bowden/sparks.htm#buzz.gif Assuming you gun...

Wonder if it would go here but it's combustion anyway. While messing around in my room, I came across some of my old notes I printed off websites that interested me. One site was this http://www.scitoys.com/scitoys/scitoys/thermo/thermo2.html (Scroll Down) Since I had some film containers in my room...

I still have the econogun but I took the ignitor off for a different project today

I've seen that one a few times. Wonder if he lost his hand? Anyway, my friend Martin Stearn and his pal Zach also though about makeing a bottle bomb only we used hydrochloric acid (sold as muritic acid in pool stores) and chlorinating tablets. My "girl" friend was also going to watch and I warned he...