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Unread 09-06-2008, 20:56
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RyanN
AKA: Ryan Nazaretian
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Re: Water Balloon Cannon Optimization

Quote:
Originally Posted by Mr. Freeman View Post
I remember someone on this forum doing tests with PVC barrels to see what can contain them if they explode. They found that duct tape does not help in any way. It will not contain shrapnel.
I know it couldn't help much. I thought it might at least keep shrapnel from flying as far or as much. Ever since I saw the remnants of our PVC barrel, I don't want it to happen to anyone else. A joint cracked and released the PVC pipe like a rocket, nearly missing the kids head and shot into the ceiling. He could have been seriously hurt or killed if his head would have been in the way. I'm not sure a 1/2" glass door will do much to stop a tank from flying through it. It may help with small shrapnel, but large pieces of shrapnel will likely go through the door if it has the chance.

As everyone here can probably tell, I'm completely against using PVC to store air. It is against OSHA regulation and it's against my common sense. It wasn't that the PVC pipe failed, it was that the even thicker coupling holding the PVC pipe together cracked and released the pipe like a rocket. It probably had less than 40PSI in the tank when it cracked. The expanding and contracting of the tank from many charges and discharges caused the PVC to weaken. Sure a brand new tank may be safe, but after using it a few times, the integrity of the PVC goes down and the tank becomes a ticking bomb. We only charged that tank to 40PSI and it took 3 years to blow (probably 300 or so charges/discharges). With 90PSI or even 120PSI it will weaken much quicker, and you are already reaching the limits of the PVC to hold air at pressure. PVC is simply not designed to hold air.

I would strongly consider finding a proper tank before attempting to even make it shoot further. Even though you feel safe, what about the people around you? Is there anyone around outside when you shoot it within 300 feet? The tank you have is like a grenade. You don't know when it will go off, and when it does, it will shoot sharp shrapnel through the air at extreme velocities.

For reference, we use an old metal freon tank. We only crank it up to 60PSI, but can safely crank it up to 120PSI.
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