SpudFiles

Well it broke. My little brother was over at my freinds house (the cannon was currently there) talking to his sister, saw the cannon in peices and told me later. I've yet to get the whole story, but I'll be taking more advice from you guys.

It probably exploded when they were using it, due to the use of pipe that says " NOT FOR PRESSURE" right on it. Seriously, when something actually states that it is not to be used for pressure, don't use it for pressure. Even DWV pipe is better than cellular core.

I was on the t connector leading to the valve. Not on a tank.

Just means the connector failed first. I haven't heard of any injuries in your posts, so I'm going to say your friend got off lucky.

Well, it's best that it happened now than when you're of building hydrogen 20x hybrids in a soda bottle. I hope you learned a lesson. Seriously, don't use non-pressure rated stuff. It's scary and dangerous. I'd recommend working with steel since it's safe and easy. I'd also recommend using a modded sprinkler valve before you attempt a piston valve. I'm working on a piston valve and I'm learning to hate myself a little more each day that passes.

Now don't say piston valves are that hard to build. There great and it makes you feel really good when they turn out fifty million times better than sprinkler valves.

Sorry, I'm not saying they're not good, in fact if I thought that I would have give up a long time ago. I'm just having terrible luck with mine due to the fact that I don't have enough time and just can't get it to work...

Well actually it broke cause he was mad at something, so in a fit of rage he threw it across his yard. And I'll post up my designs later as soon a photobucket will work for me. But I've yet to find a GOOD topic here that will help me build a piston valve. I don't really want to spend the money on a sprinkler valve, and besides, my next barrel will be 2.5 in. A sprinkler valve will limit it too much.

Well, best of wishes with your valve. I know there's a good video tutorial on BC vids. I'll try to find it if you'd like. One thing though, getting 2.5" pipe is hard. You're probably going to have to order for it.

EDIT: Ah, here's the link. http://www.bcvids.com/dload.php?action=file&file_id=4 Have fun.

I think I've seen it before. IDK. There is a local plumbing store that might be able to pick some up.