Piston problems

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iPaintball
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Sun May 06, 2007 8:28 pm

I just finished my cast-epoxy piston and I ran into a few problems.
On the inside of the tee, when the piston is closed, the inlet air would pass right into the pilot area because the piston is too short. Would I be able to fix this problem if I filed away the pvc step in the front end of the tee so that the barrel is far enough into it to see when I look throught the inlet? Or would this mess the whole thing up? I would be very appreciative if anyone could help me!!!
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iPaintball
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Sun May 06, 2007 8:46 pm

Srry, I can't post a pic.
cyanite
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Mon May 07, 2007 5:29 am

Sorry mate, but it's hard to figure out what the problem actually is, from your description (Try to post pics... would be very helpful). If you have cast it out of epoxy, why not make the piston a little longer? And I suppose you could push the barrel in a little further, but that would decrease flow. Again, post pics if you can... they would help significantly.
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spudthug
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Mon May 07, 2007 6:02 am

On the inside of the tee, when the piston is closed, the inlet air would pass right into the pilot area because the piston is too short
where are u filling it from? you cant fill it from the chamebr unless u have a spring on the piston... of course it is going to pass to the pilot. the pilot is how u set it off, the port is the barrel...
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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jrrdw
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Mon May 07, 2007 6:49 am

All the above said fix's will work, just deside witch 1 you want to use. Here's another idea -- Add a long enough center bolt to add another piston on the back to use in the pilot chamber. That will allow the flow to remain and fix your problem.

Image

Iv'e learned about this by researching Spudfiles and the Wiki. Thanks guys/gals.
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iPaintball
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Mon May 07, 2007 2:14 pm

cyanite, I can't make the piston any longer because I can only cast the piston half way into the coupler. (I'm using a coupler as a mould)

jrrdw, I'll prolly just make a new piston.
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tylerthetatertosser
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Mon May 07, 2007 2:44 pm

i thought i would have the same problem with my piston being to short because i was using a short end cap so all did was move the barrel further in the tee. so the problem you are having never occured
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