WIP Valve design

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Phirephly
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Fri Jun 27, 2008 1:50 am

I'm working on this valve as a method to create an inline valve. I'd like some input on it and any advice that I could get. Also, what would be a reliable place to get 2 and 1 inch orings?

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kablooie
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Fri Jun 27, 2008 3:44 am

Looks to me like it would work in theory, and it's something different, so that's definitely good. Some thoughts are that at least one of those lips stopping the piston would have to be extremely strong, as the slamming back of the piston would cause a lot of strain. Basically you will need a bumper and strength.

Those equalization holes I'm sure will be smaller than they are shown on the animation, otherwise too much air would pass through. Nice animation by the way.

For o-rings, ace hardware has many (at least our local one does) and you can also buy kits where you can make your own custom o-rings with rubber string (there's a better word I'm sure) bonded with super glue.
Tom
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Fri Jun 27, 2008 3:46 am

I think the piston needs a little help from a spring to reset, looks like a good idea :!:
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SNDM
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Fri Jun 27, 2008 4:23 am

That looks like a good inline valve design to me.

Kudos for the design!
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Carlman
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Fri Jun 27, 2008 5:05 am

looks very good mate, have fun!
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psycix
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Fri Jun 27, 2008 5:31 am

Nice design!
You could use a 3-way valve for the fill/pilot. Would make it easier to operate.

Only flaw is that this design only efficiently supports 1" barrels. If you would use a 2" barrel, the flow constriction would take off some muzzle velocity.
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clide
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Fri Jun 27, 2008 12:04 pm

Well, unless the piston actually seals against the stops on the left and those stops cover more area than the part that slides through the center then it is not going to work at all.

Picture the gun when it is fully charged with air. You have the full diameter of the piston worth of area pushing the valve to the right, but only the area of that ring shaped pilot area pushing it to the left. Meaning that the valve will open itself (probably with a honking sound) as you are trying to fill the gun.

A way you could get it to work would be creating a seat where those far left stops are. You would have to make sure that the area sealed off from the seat had more surface area covered than the rest of the exposed piston. It would also be a good idea to add a small exhaust hole to the area that is sealed off so a small leak wouldn't fire the valve unexpectedly. See attached picture.

Edit: clarified picture a bit.
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mac guy
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Fri Jun 27, 2008 1:40 pm

that valve looks very good. with a few tweeks it could be amazing.. let us know when you get it built and tested.
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bigbob12345
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Fri Jun 27, 2008 1:46 pm

genious design
although you could simplify it by not adding orings or equilzation holes on the 2in part. It would reseal easier and just be easier to make.
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DonTheLegend
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Fri Jun 27, 2008 6:08 pm

It looks like it will work, but you will have to be careful when you make it. Make sure that you have more area exposed to pressure on the pilot side than on the chamber side, otherwise as clide noted, it won't work at all.

Otherwise, neat design. Also, McMaster is an excellent source of o-rings, especially larger sizes. I think most hardware stores don't carry much larger than 1" but it just depends on where you live I guess
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mobile chernobyl
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Fri Jul 11, 2008 11:57 pm

It will work, a similar design is being used in paintball right now.

It may not be listed on this site, but check this site out, paintballs a little bit ahead of us in valve design.

http://www.zdspb.com/tech/misc/animations.html

your design is essentially a really simple spool valve.
clide
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Sat Jul 12, 2008 11:27 pm

mobile chernobyl wrote:It will work, a similar design is being used in paintball right now.
Good to know that paintball guns can defy physics :roll:

You could slightly change a few things to get it working, but as drawn all it will do is fart air down the barrel as you fill it.
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mobile chernobyl
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Wed Jul 16, 2008 7:46 pm

Sorry there clide buddy ol pal - I was looking at your photo and responding to his post, didn't realize you had already altered it. The smiley selection makes you seem like an A$$ btw lol.
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