Piston Valves Explained Visually

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clide
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Sun Jun 10, 2007 5:45 pm

Yep, Mauler valves are just well built barrel sealing tee valves.
It's not very expensive to build your own. If you want more flow than a 1" sprinkler then building your own valve is the cheapest solution most of the time.

You are right with your last sentence, but I would rephrase it slightly. Barrel sealing valves don't need o-rings because you don't need a perfect seal around the piston. You want to make the piston the best fit you can, and it will probably still let plenty of air through. If too much air can get past the piston then it will decrease performance or possibly not fire at all.
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chartreusesnot
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Sun Jun 10, 2007 6:55 pm

It seems like tee's always come with a lip in them to stop pipe from going to far. This makes the inside a weird pipe size, so which size of pvc pipe would best fit a 2.5 inch tee for the body of the piston. Also, in the diagram of the barrelsealing one, the equalization hole is on one side of the piston. Is this hole drilled into the tee? the piston? or is it just a beneficial outcome to not having a perfect fitting piston?
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clide
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Sun Jun 10, 2007 7:54 pm

The lip in all the tees I have seen aren't as high as the ID of sch40 pipe, so just make the piston out of something that fits in the pipe. I haven't worked with 2.5" pipe much so I don't know what fits well, you may want to start a new topic about it if you can't find anything.

In that case the equalization hole is just the lack of a seal between the pipe and the piston.
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chartreusesnot
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Sun Jun 10, 2007 8:26 pm

They aren't as high as the ID of sch40 so you are saying I should sand down whatever fits in the tee?
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clide
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Sun Jun 10, 2007 10:54 pm

I'm saying you should have some pipe glued in the side of the tee that the piston will fit in, and just make the piston out of whatever fits in the pipe. That's what I have always done.
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chartreusesnot
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Sun Jun 10, 2007 10:55 pm

oh... I see like a seat. Thats a good idea...
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MrCrowley
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Sun Jun 10, 2007 11:36 pm

chartreusesnot wrote:On BCarms, they sell these things called "mauler valves" are these like the piston valves? Do they work better or worse? and how expensive is it to make a piston valve? Barrelsealing valves don't need o-rings because air needs to get by the piston right?
thanks
Yes, they are piston valves. They will perform better then your average homemade piston. Depends how big you your gonna make it, where you live and how much pipe costs there. And yeah they don't, but having O-rings with an eq hole should increase performance significiantly.
silverdooty
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Thu Aug 23, 2007 7:54 pm

thank you for very well thought out animations. i had been wondering about the differences between the barrel sealing and the chamber sealing valves.
unfortunately now i must build launchers for each valve :cry: jk
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Thu Aug 23, 2007 8:29 pm

Can someone please explain to me why it is that barrel sealers are supposed to be better than chamber sealers?

I assume better means they open faster...and looking at these flash diagrams it would seem that the barrel sealer has less surface area than the chamber sealer on the "open side" of the valve (the lcoation where when force is applied it will open the valve). And so surely the valve with the largest surface area means it will open faster?
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BigJon
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Thu Aug 23, 2007 9:09 pm

I think barrel sealers are supposed to be better because there is less dead space involved.
clide
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Fri Aug 24, 2007 12:10 pm

Gepard wrote:Can someone please explain to me why it is that barrel sealers are supposed to be better than chamber sealers?

I assume better means they open faster...and looking at these flash diagrams it would seem that the barrel sealer has less surface area than the chamber sealer on the "open side" of the valve (the lcoation where when force is applied it will open the valve). And so surely the valve with the largest surface area means it will open faster?
What really gets the valve moving fast is the jump in surface area that the piston encounters right after it starts to move back. The way these are drawn, they would both have the same surface area exposed right when they start to move back. The difference is that the barrel sealer will have a much lower pilot pressure when the piston triggers because of the lower surface area exposed on the sealing face before the valve began to move back.
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CannonCreator
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Fri Aug 24, 2007 12:22 pm

Great job! this definatly Has to be a sticky.


Uh.... dude? It is a sticky..... has been since it was posted..... and btw, it's "definitely".
Peace,
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The Kid
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Sun Sep 30, 2007 8:41 am

man that is frieking sweet. i sort of understood them before but now i understand them a whole lot more, YOU RULE CLIDE
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Fri Oct 12, 2007 4:19 am

Ok so is the sealling face(on the barrel seeling) like a circle of rubber or something that goes around the pipe seeling it. and the pipe is blocked then you exhaust it and pressure builds on the seeling face and it gets puched back and air goes out the barrel pushing the projectile with it?
Cheers Nato
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MrCrowley
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Fri Oct 12, 2007 4:26 am

Pretty much, this may also help you:
http://www.spudfiles.com/forums/how-to- ... 10381.html
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