Defective elbow almost kills me...

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homeflake210
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Yeah, so I filled my cannon up (the barrel wasn't attached) to about 115 psi, took it outside to do a dry fire. I fire it and instead of makeing its usual crack I get a massive BOOM, the valve flies about 3' high and a large piece of a 2" Sch. 40 pressure rated elbow flies through my hair and goes through the screen on my screen porch 20 yards behind me. The only reason I can think of why it might have did this is that the part was defective, I put the male adapter on with a pipe wrench (before glueing) to ensure I wouldn't crack the elbow or any other parts of my cannon trying to screw it on tight...

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PAspuder
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you are a lucky person. I had one do that before, but my blew off because i had too much weight in the baral. Yours may have been defective. how long was the barrel? did you have alot of weight hanging, puting pressure on that point of the gun?
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iPaintball
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Whoa. Thats pretty messed up...
The only way I could think to be the reason for that happening is that when you fired it, the air recoil might have stressed the elbow to the point of failure.
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pyromaniac
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Dang your uber lucky you didn't get hit.

Times like this really turn people off the sport.
(if trampoline is an olympic sport i think spudding should be a sport)
:pottytrain3:
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homeflake210
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PAspuder: The barrel wasn't even on the gun.

Da Pneu Kid: Well, people have fired cannons much larger than this though without their elbows giving... I wonder if not having the barrel attached put more stress on the valve?
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pyromaniac
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I feel so stupid now.

It looked like it was a coupling that broke.
So i thought why is his gun going to be in a trianglish form.
:puke:
:pottytrain3:
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iPaintball
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That's what I meant. If the barrel wasn't attatched, the jet of air blasting out would've put WAY more torque on the elbow than if there had been a heavy counterweight (barrel) attached to it
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paaiyan
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Wow, that sucks bigtime. You gonna be able to repair it?

Btw, I have a watch just like that. 8)
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pyromaniac
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Ya the whole upside down watch thing........ i dont get it.

he took the picture at 5:06 lol
Last edited by pyromaniac on Thu Apr 12, 2007 5:00 pm, edited 1 time in total.
:pottytrain3:
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homeflake210
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Yeah I'm going to cut grooves into the pieces of the elbow left (with a dremel), then pry them off, sand off the paint, and put a new elbow on.... Walmart watches kick ass.
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shud_b_rite
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Other than the big crack in ya cannon, it looks like a pretty sweet firing setup.
Airbeds... so many different uses
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VH_man
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It might have been stress on the parts.... i know that that can seriously weaken things. a whole full air chamber supported by a 2 inch elbow has a good 500 lbs of tourque on it..........
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MisterSteve124
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Yeah I have heard from many people that not having a barrel on and firing puts a lot of stress on the valve so that was probably it. It makes sense when u think about it.
Matheusilla
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C'mon guys/gals, plastic? ABS or PVC, it's gonna fail some day. I really don't know what to say, personally I just accept that in any situation it could fail; it's only realistic.
clide
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Yep, firing a high flow valve with with a big chamber and no barrel puts a surprising amount of stress on the gun. I have had nearly that exact same failure before. Except my valve landed in a way that also broke the valve. :(
http://www.spudfiles.com/spudtech_archi ... 5043#25043
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