Page 1 of 2
Piston Valve Question
Posted: Wed Oct 17, 2007 1:25 pm
by dapallox1
Which is better, a barrel sealing piston valve, or chamber sealing?
Posted: Wed Oct 17, 2007 2:12 pm
by MrCrowley
Good question, though it has been asked many times before.
I think it was barrel sealers open slower but have higher flow, chamber sealers open faster but have less flow.
I'm not 100% on that, you should search and find out for yourself.
Posted: Wed Oct 17, 2007 2:17 pm
by dapallox1
Well, I'm looking for as much power as possible out of my cannon under construction. My main goal is for it to be really loud, and shoot a golf ball (or similar projectile) as far as possible.
Posted: Wed Oct 17, 2007 2:23 pm
by MrCrowley
Barrel sealers are a lot easier to make.
Look at my barrel sealer golfball cannon, capable of 400yards with a 90cm barrel
http://www.spudfiles.com/forums/viewtop ... tml#100616
Posted: Wed Oct 17, 2007 4:32 pm
by jrrdw
Show off! But i truely approve.
Welcome to Spudfiles dapallox1, when you get you cannon built, show it off to us, video's are the best, if kept short.
Posted: Wed Oct 17, 2007 4:54 pm
by dapallox1
well, i have already posted two cannons on one, but i used DWV elbows and the second one, and i have yet to mod the sprinkler valve. But, my new one that i designed will be a double chamber grounded one. And I want to make it as powerful as I can at the moment with the money i have. And thank you for the welcome!
http://www.spudfiles.com/forums/my-firs ... 11189.html - My first two cannons
Posted: Wed Oct 17, 2007 5:34 pm
by clide
Which one opens faster depends on this size of the piston and piston seat, but given a set piston size then the most powerful valve you can make with it would be a barrel sealing valve.
Posted: Wed Oct 17, 2007 5:46 pm
by dapallox1
im going to build it into a 4" tee.. and the design i have drawn up uses a barrel sealing method, so that is great for me. Thanks alot. Do you know if a 3" end-cap would fit down a 4" tee?
Posted: Wed Oct 17, 2007 5:58 pm
by Vanlandinghale
3" end caps actually fit really snuggly in most 4" tee's. I'm thinking of the same thing for my cannon.
Posted: Wed Oct 17, 2007 6:25 pm
by spudgunnerwryyyyy
3" caps fit well in shc40 4" pipe, not the tee. Also some sanding is needed to get the cap to fit in the pipe. A curved seal is sometimes better.
Posted: Wed Oct 17, 2007 7:25 pm
by dapallox1
Well, if it fits inside the pipe with sanding, then it should fit perfectly into the tee shouldn't it? If not, then what could I use?
Posted: Wed Oct 17, 2007 10:21 pm
by jackssmirkingrevenge
Which one opens faster depends on this size of the piston and piston seat
Also weight of the piston, size of pilot chamber, pilot valve flow rate/opening time, size of equalisation hole...
I think it was barrel sealers open slower but have higher flow
Where did that come from?
Posted: Wed Oct 17, 2007 10:27 pm
by dapallox1
It will be built inside of a 4" tee and I'm going to use a 1" sprinkler valve to pilot it
Posted: Wed Oct 17, 2007 10:31 pm
by jackssmirkingrevenge
Sounds good. Remember, the piston only has to travel back 1/4th of the barrel diameter for maximum efficiency, provided the T is reasonably wider in diameter than your charrel in the case of a chamber sealer.
Posted: Wed Oct 17, 2007 10:38 pm
by dapallox1
Its going to be a barrel sealer. Would it matter if I had more space for the piston to travel back?