SpudFiles

I found a 3/4 pvc coupling that already has an o-ling build inside.
Too bad it's made of pvc if not it would make a neat hybrid. However, that didn't stop me from buying it, so I've saved a transparent plastic bottle for a while, it's made of the same material as coke bottles, but a lot thicker.
So I sanded down the neck of the bottle with a dremel, made the threads on a metal 3/4 adapter then installed the coupling on it.
The bottle is around 1L so it shouldn't be too loud and I'm hoping to make it a easy to use and reliable little cannon to entertain my friends. To do that I thought I'll need a pump for venting and easy fuel injecting, that's why I made a 1/4 thread at the bottom and installed a push to connect fitting, it will be connected to a 5/2 valve witch is connected to fuel meter and a pump.
I didn't want to wast a taser on this so I used a used Bic BBQ lighter, very good quality, never failed to make a spark.
So far I made it work, "BANG" right on the first click, not finished yet of course.
High speed video:
[youtube][/youtube]

Nice!

Come on, I'm sure it can take 2x... go hybrid!

jackssmirkingrevenge wrote:Nice!

Come on, I'm sure it can take 2x... go hybrid!

I would, but there are leaks. I could took some time and fix the leaks with epoxy but as it'll mainly be used for entertainment just to show the flame and maybe some crashed potatoes, power never was my goal on a combustion. Also I've to be responsible for my friend's safety, I got to go that extra mile on safety.

It's not about power, just curious to see the if the burn pattern varies in a pressurised environment.

This is the closest I've gotten to seeing it in a hybrid, through the epoxy endcap:

[youtube][/youtube]

Kind finished the fuel meter, missing the fuel meter gauge still.
The "thing" on the left is a flow control valve to reduce the flow from the propane tank. The tiny gauge is for viewing the pressure inside the pressure tank.

Well, finished the meter and has all the rest planed.
The 5/2 valve didn't work the way I wanted, but well, I can live with it the way it is now. (too lazy to find a solution, it's bloody hot in my work shop)
BTW I used 2 layer of foil rather than 1 for once and I definitely got more power.

Done. Not the most advanced cannon but it has all it's needed to fire.
The bottle under the barrel is propane tank, the other grey "tube" is a cheap pump for filling balloons, high volume. Not pressure rated, but it's also isolated from the chamber when firing.
Once it's cooler outside I make a video.
One old question, can I use one of these 10 bucks compressor regulator with propane? Because a small regulator would really be handy now.

Oh, pretty hot!
I especially like the transparent combustion chamber!

But you're afraid to put your head above U_u ?!

The bottle is pretty thick, so as a combustion I actually believe it's safe, but I don't shoulder fire it anyway Be able to see the gas burning is basically all my reason building this.

Ah ok, if an accident will...

That aluminum ring around the chamber provides extra safety