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Posted: Mon Aug 07, 2006 9:51 pm
by MisterSteve124
why did you hit it with a hammer for a test?? what would that tell u i think air and a hammer are a bit different

Posted: Mon Aug 07, 2006 11:42 pm
by Steve-
um, I don't think the water idea wouldn't work. Since we are using these tubes for air, they must be tested with air, not water. As you said, the pressurized air has more energy so therefore we have to be careful about what pressure we put it under. I know the safety margins are high but those are for water pressure and you always have to take that into account.


ps. you could just put the chamber in a big box of water, that would slow down the flying pieces ALOT and depending on how big your box of water is it could stop all the flying pieces.

Edit: I'm sorry if I'm all wrong about this... I have been wrong about a lot of things lately.

Posted: Tue Aug 08, 2006 12:25 am
by frankrede
MisterSteve124 wrote:why did you hit it with a hammer for a test?? what would that tell u i think air and a hammer are a bit different
Drop a pvc spudgun your F*ckd. Drop abs it will bounce back into your hands(exaggerated.)

Dont drop pressurized pneumatics. Bam!

That is avoidable by sleeving the pvc with abs.
But dont use abs in pneumatics,only as a sleeve in pneumatics.
My steel box idea worked fine.

Posted: Tue Aug 08, 2006 2:38 pm
by cannon freak
Filling the chamber with water and then pressurizing it would work just fine, there is more energy stored in pressurized gas but what you are trying to do is just pressurizing the chamber and whether it be water or air its the same, unless you are going to drop it and see what happens or something then you would need air to get the proper results.

Posted: Tue Aug 08, 2006 2:42 pm
by Shrimphead
You are right about pressurized air having more energy, Steve-. But for pressure testing, a pipe filled with water at 100 psi is just as likey to burst (or to not burst) as a pipe filled with air at 100 psi. And when a pipe filled with water bursts, it isn't as violent as one filled with air. Less risk, same outcome.

About putting the pipe in water, I want to know how much of an effect that would have on the pipe. Because something submersed is being pushed on from the outside with more force than in open air.

Posted: Mon Aug 21, 2006 8:02 pm
by boonedog132
guys before i knew about pressurse rated pipe... i ran my cellular core pipe up over 100psi so dont say it can't be done i can take a friggin picture of the pipe if i have to

Posted: Mon Aug 21, 2006 9:12 pm
by Shrimphead
Ya, but the rest of us care about our safety.

Posted: Mon Aug 21, 2006 9:38 pm
by ProfessorAmadeus
Just dont use it any more. Since you know about rated pipe use it.

Posted: Mon Aug 21, 2006 11:38 pm
by frankrede
Like I said,I dont reccoment using abs in pneumatics,Imj just saying that It can take the pressure but still don't use it.

Posted: Tue Aug 22, 2006 6:37 am
by rna_duelers
I took 3/4 abs pipe upto 130psi no troubles and used it alot in a small pneumatic.

Posted: Tue Aug 22, 2006 7:01 am
by Dom
rna_duelers wrote:I took 3/4 abs pipe upto 130psi no troubles and used it alot in a small pneumatic.
Hey, if you want to die young, it's your call.

Posted: Tue Aug 22, 2006 9:08 pm
by frankrede
rna_duelers wrote:I took 3/4 abs pipe upto 130psi no troubles and used it alot in a small pneumatic.
Hmm,the only abs at my lowes is cellular core,and it doesnt go smaller than 2 in. I wish i had some 3/4 because it can take more pressure than 2 in. But ya in a small pneumatic abs doesnt sound that bad:)

Posted: Tue Aug 22, 2006 9:12 pm
by ProfessorAmadeus
I dont even trust my pvc to that pressure. Im a pansy

Posted: Tue Aug 29, 2006 9:47 pm
by dinsdale
i finished my cannon about a day before i found this site, its a pneumatic sprinkler valve in-line cannon made of sch 40 dwv abs pipe (2") i run it at 95 psi with no problems.
my next cannon (a very large coaxial ) will be sch 80 pvc, but for now the abs doesn't scare me

Posted: Thu Aug 31, 2006 1:52 am
by Pete Zaria
Dinsdale, I really wouldn't suggest using ABS in a pneumatic in the first place, but using 95 psi seems like playing Russian roulette. It's true that ABS has pretty mild failure characteristics; it tends to rip clean and not send much shrapnel. But 95psi is way more than it's meant to take, especially in hot or cold weather, or after repeated firings.

To be honest, If you do it, it's your own choice. I just hope nothing happens to you, because if things start showing up in the news such as "Teenager killed by plastic shrapnel from home-made cannon", spudguns will become illegal. Don't get spudguns outlawed for everyone, OK? :)

Peace,
Pete Zaria.