Piston Valve Question

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dapallox1
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Wed Oct 17, 2007 1:25 pm

Which is better, a barrel sealing piston valve, or chamber sealing?
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MrCrowley
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Wed Oct 17, 2007 2:12 pm

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.
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dapallox1
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Wed Oct 17, 2007 2:17 pm

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.
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MrCrowley
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Wed Oct 17, 2007 2:23 pm

Barrel sealers are a lot easier to make.

Look at my barrel sealer golfball cannon, capable of 400yards with a 90cm barrel :shock:
http://www.spudfiles.com/forums/viewtop ... tml#100616
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jrrdw
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Wed Oct 17, 2007 4:32 pm

MrCrowley wrote:Barrel sealers are a lot easier to make.

Look at my barrel sealer golfball cannon, capable of 400yards with a 90cm barrel :shock:
http://www.spudfiles.com/forums/viewtop ... tml#100616
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.
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dapallox1
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Wed Oct 17, 2007 4:54 pm

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
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clide
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Wed Oct 17, 2007 5:34 pm

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.
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dapallox1
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Wed Oct 17, 2007 5:46 pm

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?
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Vanlandinghale
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Wed Oct 17, 2007 5:58 pm

3" end caps actually fit really snuggly in most 4" tee's. I'm thinking of the same thing for my cannon.
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spudgunnerwryyyyy
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Wed Oct 17, 2007 6:25 pm

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.
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dapallox1
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Wed Oct 17, 2007 7:25 pm

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?
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jackssmirkingrevenge
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Wed Oct 17, 2007 10:21 pm

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?
hectmarr wrote:You have to make many weapons, because this field is long and short life
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dapallox1
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Wed Oct 17, 2007 10:27 pm

It will be built inside of a 4" tee and I'm going to use a 1" sprinkler valve to pilot it
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jackssmirkingrevenge
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Wed Oct 17, 2007 10:31 pm

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.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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dapallox1
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Wed Oct 17, 2007 10:38 pm

Its going to be a barrel sealer. Would it matter if I had more space for the piston to travel back?
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