How much pressure

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carlbelcher
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Mon Aug 14, 2006 10:08 pm

The difference is that non-pressure rated pipe is not tested for pressure which means that it might hold 10,000psi or it might burst at 10psi. People have had pressure rated pipe burst well below it's rated pressure.

The point is that you could probably get away with up to about 70psi which is a common pressure for combustions to reach, but there is no guarantees.

If it does decide to explode it's very likely that it will injure or even kill you.
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cannon freak
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Mon Aug 14, 2006 10:10 pm

I supose it would be safe enough to put a simple barrier between you and the gun so if it goes no harm done.
boonedog132
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Mon Aug 14, 2006 10:16 pm

i just looked it isn't pressure rated it is... cellular core what does that mean?
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carlbelcher
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Mon Aug 14, 2006 10:19 pm

That's as bad as it can get! Cellular core pipe has foam walls instead of solid PVC. It's not safe at any pressure!
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boonedog132
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Mon Aug 14, 2006 10:22 pm

SHIT omg this sucks...i've been using this all day... the most i ever put in was 90 psi but i was scared to go more and now i'm glad i didn't ... wouldn't it already have busted by now tho if it was gunna?
boonedog132
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Mon Aug 14, 2006 10:29 pm

are there any signs like... when it might be close to bursting? there are leaks around the valves...
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Atlantis
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Mon Aug 14, 2006 10:29 pm

If it's cellular core, which yours can't be, that basically means it's like styrofoam, filled with air bubbles.

Look at the cut edge of the pipe so you can see a cross section of the pipe, I believe DWV has a color difference between the outer walls and the "filling". I know at least cellular does.

Maybe you can try wrapping some chicken wire around the chamber, that should catch any shrapnel if it does explode.
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boonedog132
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Mon Aug 14, 2006 10:32 pm

ya i'm pretty sure it is cellular... i remember reading that when i bought it...i will definatly put the chicken wire around it....and i am wearing glasses and gloves from now on for sure
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carlbelcher
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Mon Aug 14, 2006 10:33 pm

Not necessarily, over time fractures can form in the pipe from the pressure causing it to be a "ticking time bomb". I don't think it's safe to use, but it's up to you. It might never explode, but then again it might at any time. I don't trust cellular core pipe at all!

I really hate to tell you not to shoot it, but I really don't thinks it's safe.

If you do want to shoot it, I would keep the pressure under 50psi.
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boonedog132
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Mon Aug 14, 2006 10:39 pm

ya i know but now that i've went over 50 psi i dont think i can go back lol... i will keep a close eye on the pipe for cracks... and as soon as i get to a store i'm gunna by some real PVC pipe.. i'm going to wrap it in chicken wire ...i dont think that i can NOT shoot it right now i'm hooked lol
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Shrimphead
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Mon Aug 14, 2006 11:30 pm

I wouldn't use that gun. I wouldn't even use cellular core in combustions. It would scare me too much.
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CS
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Tue Aug 15, 2006 12:00 am

"People have had pressure rated pipe burst well below it's rated pressure."

-What tests?

boonedog132, sounds like you got the syndrome of making your cannon look like it got left unfinished for stucco.
;-)

"That's as bad as it can get! Cellular core pipe has foam walls instead of solid PVC."

-A 'foam' like interior, contained by thin sheets of 'solid' PVC.

I still dont suggest the usage of cellular core, but in all honesty we contain ~125PSI within the ~.015" thick walls of pop bottles. Which im sure is close to the thickness of 'solid PVC' containing the foam interior in cellular core pipe. What in thrives this thought that one is able to contain ~125PSI, and the other not to a even rumored ~40PSI?

[Such questions have been brang about after rumors such as the whole PVC not showing in X-Rays...]
Nereth
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Tue Aug 15, 2006 7:31 am

if its pretty thick, you probably missed the rating. Go out and measure the mm thickness (fine, inches, damn americans.) and the diameter of the pipe, and we can at least tell you if its drainwater. I can maybey give you an idea of its pressure rating by australian standards too, but i dunno how it converts.
boonedog132
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Tue Aug 15, 2006 10:32 am

ok ... it is just over 11inches all the way around the pipe...and the walls are 1/8 of an inch thick.... and i drove a nail into the "foam" stuff and it seems pretty damn hard to me lol
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Shrimphead
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Tue Aug 15, 2006 1:39 pm

If it's cellular core, don't use it. And Pimp, you can't compare different plastics like that. Soda bottles have to be able to hold pressure because of the carbonation. Cellular core wasn't made for pressure. That's like saying a 1/2" thick cardboard tube should hold pressure because a 1/8" thick metal pipe can.
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