hammer valve design

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JDP12
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Thu Dec 08, 2011 6:22 pm

Slightly new twist on the hammer valve design proposed by BTB... It's explained within the diagram, and as far as i can tell it should work fine, the only difference is how the air flows through the valve, just wanted your final thoughts.

Already calculated necessary o-ring sizes and tube sizes.

Again keep in mind, none of this is proportional, especially the location of the hole in the tubing that allows air into the actual valve.
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Hawkeye
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Thu Dec 08, 2011 6:33 pm

In both diagrams you guys drew shouldn't there be dark blue surrounding the o-ring section?
You may find it isn't quite as easy to sleeve stuff together and also have NPT fittings.
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JDP12
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Thu Dec 08, 2011 7:02 pm

Eh, the idea behind this is nothing is perfectly sleeved inside each other, the yellow tube depicted is a smaller diameter than the black tubing to allow air flow around it...So a perfect sleeve fit is not necessary.
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Hawkeye
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Thu Dec 08, 2011 7:12 pm

I meant more that having the tubes run inside a larger one in any way doesn't really match the way a NPT fitting is threaded.
The yellow tube can't be threaded onto the inside of the T and after the black tube is threaded on there really isn't a way to now have a larger tube encircle it.
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JDP12
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Thu Dec 08, 2011 7:22 pm

the yellow tube will be epoxied into the other end of the tee, so it won't be threaded at all. Clearly my diagram wasn't clear, i tried to explain it in words.

Imagine its a 3/4" tee, with a 3/4" nipple screwed into the left, the black tube is epoxied inside the NIPPLE not the tee. On the right side of the tee is just the yellow tube epoxied into the center.
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Hawkeye
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Thu Dec 08, 2011 7:34 pm

I see. Not sure about your way of actually holding the black tube in position and having it stay clear of the wall of the 3/4 nipple? It will need to taper.
I don't care for the idea of epoxy having to withstand the constant hammering.
Some combination of threading and soldering seems like a better idea.
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JDP12
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Thu Dec 08, 2011 7:42 pm

black tube is epoxied into the nipple, the green is epoxy. notice the epoxy is to the right of the hole so air can still flow into the cahmber..

The black tube is of a smaller diameter than the 3/4" nipple..
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the unit
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Thu Dec 08, 2011 9:56 pm

Why even have the black sleeve, why not just use a machined brass nipple?
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JDP12
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Thu Dec 08, 2011 9:57 pm

look at BTBs original counterbalanced hammervalve.. it has to be smaller in order to allow air to get into the valve. you could do it other ways, but this is a nice, streamlined way of doing it.
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