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2liter an 20 oz bottles

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Unread postAuthor: MrCrowley » Thu Dec 21, 2006 6:13 pm

judgment_arms wrote:Coke bottles are rated to about 150psi plus they don’t frag… I once got a 2 liter coke bottle to 100psi and shot it with my pellet gun, nothing happen beyond a loud hiss and a small hole. So worst case scenario: loud pop.


Well the ones down here do, that kid got nailed, cuts all over his body and face and there was a news report on it and everything and proof, it wasn't some myth. It was about 2years ago so I forgot what was the cause of it but judging by the picture of the kid he will be scared for his life.
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Unread postAuthor: CS » Thu Dec 21, 2006 6:13 pm

Well what if the ditz that made your bottle was lazy, and possibly tossed some of a F-ed up batch in there? This is a common practice, as a yellowish tint on PVC fitting indicates this. In such a case your bottle is going to be weaker, versus that of one undergoing all the correct procedures.

Obviously, it comes down to ones standards. I personally don’t do things with a 20% safety factor, I would at least strive for a 100% or if not more. Once again what is wrong with 'safer' materials such as PVC/ metal? I know we may be stuck in this rut of looking like white trash, but I mean spend a bit more money to ensure safety.

.:EDIT:.


"Coke bottles are rated to about 150psi plus they don’t frag" ~judgment_arms

What the hell? Where did you get such a figure? As clearly there is no pressure rating expressed on the bottle itself, and I think if there was such a number, Id think it to be out of the 'regular' persons means of gathering information. Wow, talk about pulling stuff out of your ass... [I know I sound I like a asshole, (Yeah the one your pulling stuff out of) but don’t throw out bullsh*t figures, for some random user to pick up and from such result in injury.]

As in the case MrCrowley mentioned, it appears that the incident was as a result of manufacturing error. This is exactly why safety factors are imposed. Although as much as it is tried to be avoided, you simply cant prevent such chances by imposing higher safety factors. You can significantly reduce the chance, but not eliminate it. The same exact reason why we here in the hobby suggest member to impose there own safety factors, and abide by ones given.
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Unread postAuthor: Recruit » Fri Dec 22, 2006 4:00 am

Pimpman is right we should do our best for safty reasons. We all know how easily pvc can kill you if you over pressurize it causing it to blow up or drop it when it is pressurized once again causing it to blow. So why not spend a few more dollers on your saftey?

Oh and may be he had bought a coke in a glass bottle. Because if I remember right they still sell them in glass bottles and glass frags really bad.
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Unread postAuthor: MrCrowley » Fri Dec 22, 2006 4:12 am

Umm no, how would a glass bottle blow up with coke inside? Glass coke bottles are very rare here, it was a 600ml bottle(plastic) of coke that exploded next to him in his car.
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Unread postAuthor: Insomniac » Fri Dec 22, 2006 4:12 am

Well I ALWAYS do a pressure test with EVERY bottle I use, and I always wear sunglasses 'just in case' ( Yes I know sunnies arn't safety goggles but any frags from a soda botttle wont have the energy to smash the glasses because I try to hold it away from my face) So far I haven't managed to pop a bottle even when I wasn't using a pressure guage and just pump till I got tired ( That was a VERY dangerous practice). Even though my gun doesn't have a guage, I used an external tire guage so I know how many strokes it takes to get to 80 psi on my pump.
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Unread postAuthor: judgment_arms » Fri Dec 22, 2006 4:28 pm

Ok I just pressure tested two 2 liter bottles, the results:
The first was a Coke bottle, at 120psi it just swelled a little, when I disconnected it from the quick-connect it shot off like a rocket. So be careful.
The second was a “Sam’s choice” cola bottle(China-mart brand) that we’ve had for over a year full of water(also a over a year old) and at 100psi it also did nothing when I disconnected it from the quick-connect it just set there and sprayed water like a fire hose.
I re-pressurized it back to about 100psi and threw a ¾”x5’ dowel rod at it like a javelin, no frag, the cap(which had the quick-connect in it) blew off, and the bottle shot off like a rocket and flew at ground level about 30 yards. (The quick-connect was still in the air compressor hose) the bottle looks to be strong enough for many more pressurizations. Once again IT DID NOT FRAG! I would say that a 2liter bottle would be safe at 100psi, there were no stress marks, no cracks, and no bubbles. The cap, on the other hand, I would not trust at this pressure. The 150psi rating I found on a web site about water rockets.
Any questions?
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