Help with piston

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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Hubb
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On my newest design, I am wanting a tee piston, however, I want to add pipe to all sides of the valve. Is there a recommended way to do this fairly easily or am I going to have to block the pipe, drill holes and such?

I'm pretty sure the description is kind of vague so I included a diagram to help better explain it:
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jrrdw
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What don't you understand about it? Looks standerd to me. Where your asking for help, are you trying to get the pilot pipe into the center of the tee? You have to grind/dremal/sand the pipe stop out of the tee. The barrel needs to be more to the center also. Or the chamber air wont push the piston back.
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SpudUke5
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hubb017 wrote:I want to add pipe to all sides of the valve
Im not sure i understand that but you need to add pipe on all parts of the tee for a working setup. You dont have to center that 2 inch pipe (the pilot one). Just push it in all the way. You can make a small piston and push the barrel back down farther so that you can create minimal pilot space for best performance but it looks standard to me too. This was my first design on my first "good" pneumatic. You can just drill holes and tap them with screws. It should be fairly easy even though i have never done it before.
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MrCrowley
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Are you trying to get a piece of 2" pipe all the way into the tee so it's up against the lip(pipe stop)?

Well you just force the pipe in, that's that. May require a hit from a mallet. Then you can use a deodorant can as a piston.

And yeah move the barrel further centre.

Since you're using a 2" setup have you read this?
http://www.spudfiles.com/forums/how-to- ... 10381.html
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Hubb
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Maybe this more detailed diagram will help explain things:
Image

On the right side of the diagram is a cap. The piston rides on a piece of pipe. What I want to do is extend the pipe that the piston rides on without increasing the pilot volume. Is there a way I can do this, maybe by putting the piston in a different location to avoid having to use drill bits, hoses, epoxy, etc?
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MrCrowley
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Fill it with expanding foam then drill a hole for the pilot setup and spring, which you don't need unless filling from the chamber, and it can be a pain finding the perfect spring, so I usggest you don't bother.
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Hubb
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In my current design, it will not need the spring in the pilot area. Also, the expanding foam should make for a nice bumper. The only problem I see with using the expanding foam, however, would be setting it to adjust for piston travel.
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MrCrowley
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Well once its set, you should be able to cut some of it away or sand it off. And I would have something else for a bumper for extra measure, the foam may crack or shatter.
Image

That's what happened when I forgot to put the bumper in.
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Hubb
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I was planning on a small piston valve (1" tee). I used a 2" in the original post as an example. Using a lightweight piston, do you think I would still need an extra bumper?
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MrCrowley
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Probably not, but you can loose some pilot volume with a big bumper.
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