Oxygen Propane Cannon

[enauman]

Regarding the mixing of the gasses, I wanted to keep the gasses separated until they were in the chamber. Believe me, they get mixed well enough. This thing is as loud as an artillery piece as it is. Besides the stainless steel tubing and Swagelok fittings look cool. The cannon looks as ominous as it sounds. My apologies for not posting pictures yet. The whole thing is shrink wrapped for storage and I haven't had the time to dig it out. I promise I will get to it this week. Maybe tomorrow. I don't recognize the post about construction mentioning Design News. The cannon was featured in the Gadget Freak contest in the magazine. Here is a link to the Magazine that has a couple of sketches and a picture taken at night. I don't know why the feature picture is no longer on the site. It was kind of corny. They had me put on an old WWII helmet and goggles to look like some crazy guy. We dialed the oxygen way back to make the flame yellow for the photographer. The photo shoot for the magazine was done way out in the desert north east of Palmdale. The guys from the magazine got a big kick out of it. We must have fired it 40 or 50 times. Even in the flat desert it had several echo reflections the first of which was a couple of seconds after the blast.

http://downloads.deusm.com/designnews/2 ... ctions.pdf

[jackssmirkingrevenge]

clucking bell... surely you must have been tempted to load a projectile though?

[enauman]

As a matter of fact, I welded a steel grid across the mouth so no one could accuse me of doing just that. I figure the noise alone would cause enough problems...

[matti]

have you got any video of this cannon shooting ?! i would like to see and hear

[jackssmirkingrevenge]

As a matter of fact, I welded a steel grid across the mouth so no one could accuse me of doing just that.

Phase 1. Sack of potatoes + steel grid
Phase 2. ?
Phase 3. Fries

[Technician1002]

I read your description. Nice write up. On the one I'm planning, for the flashback arresting, right at the metering ports would be a expansion chambers so any blowback is contained in the small chambers. The output of the mixing tube to the chamber will have a reed valve much like that used in pulse jets. This limits the quanity of blow back and the very short small diameter mixing tube would limit the energy that can blow back into the expansion chambers. The Oxygen line would have a check valve on the hose to the chamber to prevent hose ignition. The Propane line does not need one as it is not unstable like welding gas. Both chambers would have rubber stoppers that would blow out in an overpressure condition.