Piston Valves Explained Visually

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octane89
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Tue Oct 23, 2007 10:46 am

Can someone answer this for me-
Is it possibly to have too much pilot volume? I have a 3" Tee, and the pilot volume is about the size of a 3" cap.
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Pete Zaria
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Tue Oct 23, 2007 10:53 am

octane89 wrote:Can someone answer this for me-
Is it possibly to have too much pilot volume? I have a 3" Tee, and the pilot volume is about the size of a 3" cap.
Yes, too much pilot volume is a common problem. A larger pilot valve does help, though it's best to try to reduce this volume somehow, either by re-designing the valve or filling the volume with something (foam anyone?).

A picture would be helpful...

Peace,
Pete Zaria.
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octane89
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Tue Oct 23, 2007 10:58 am

I'll have a pic soon and better explanation, but It's a new type of sealing piston Im working on, and where the piston slides back is the pilot volume (obviously), but I don't want to restrict the flow by not having it open enough.
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octane89
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Tue Oct 23, 2007 11:23 am

Here's a pic to help get an idea of what Im doing.
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Here's what it looks like together. The cap and tee will be held together by a 4" coupling.
Here's what it looks like together. The cap and tee will be held together by a 4" coupling.
bar-valve.JPG (36.66 KiB) Viewed 4114 times
Here's what I have so far. I haven't finished everything yet so so try to imagine it a bit. Hence why I did the paint drawing.
Here's what I have so far. I haven't finished everything yet so so try to imagine it a bit. Hence why I did the paint drawing.
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jackssmirkingrevenge
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Tue Oct 23, 2007 11:28 am

Yes, too much pilot volume is a common problem. A larger pilot valve does help, though it's best to try to reduce this volume somehow, either by re-designing the valve or filling the volume with something (foam anyone?).
words of reason, music to my ears :)

Octane, the disc that seals with the barrel needs to be the same diameter as your rear disc otherwise it won't be stable and won't work.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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octane89
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Tue Oct 23, 2007 11:33 am

Thats something I figured when I started to make the seals. But I have that part figured I believe. I was just gonna make it the same size, but cut away some of the unnessecary sections to allow it to "flow" back easier.
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jackssmirkingrevenge
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Tue Oct 23, 2007 11:40 am

Apologies for the sh!te paintshop, but you mean like in the attachment? that would work well.
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piston.JPG
piston.JPG (21.16 KiB) Viewed 4105 times
hectmarr wrote:You have to make many weapons, because this field is long and short life
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octane89
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Tue Oct 23, 2007 11:44 am

Yea, essentially the same unless I cut it differently.
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wangpushups
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Sat Nov 24, 2007 11:49 am

This helped me out a lot, thanks.
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f.c
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Tue Dec 11, 2007 10:03 pm

the coaxial design doesn't seem to be showing up just my luck considering i needed it.
can i be a sasquatch ?
Hawkeye
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Tue Dec 11, 2007 10:29 pm

Too bad that's the only coaxial diagram on here.
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MrCrowley
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Tue Dec 11, 2007 10:39 pm

f.c wrote:the coaxial design doesn't seem to be showing up just my luck considering i needed it.
The co-axial animation is working for me, your talking about the one on the front page right?
clide
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Tue Dec 11, 2007 11:36 pm

f.c wrote:the coaxial design doesn't seem to be showing up just my luck considering i needed it.
Not sure why it wouldn't be working, Try <a href="http://gbcannon.com/flash/coax.swf">this link</a>

Also the theory behind all of them is the same, so using another one would probably still let you learn the concept.
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f.c
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Wed Dec 12, 2007 1:52 am

thank you. its great to see a forum where people actually help each other out spudfiles get a 10/10 in my opinion.
can i be a sasquatch ?
anthony5640
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Sat Jan 12, 2008 8:54 pm

how do i make a piston?
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