SpudFiles

Soda bottles are not rated, but they ARE designed to hold the pressure that carbonated drinks can produce. Soda bottles will hold lots more than somthing like water bottle or a shampoo bottle, which were not designed to hole any pressure.

Alright that makes sense joannaardway, thanks.
Actually water bottles will hold pressure too, not as high as soda bottles, I think i got an arrowhead water bottle to 130 psi before it "popped" and a dasani to 150 psi.

mitchza89, what is this poly pipe? and how did u attach the coke bottle?

also has anyone here used a product called "jb(or was it jd?) weld"? or something like that, it supposedly can hold engine blocks together

Yeah, Its great stuff. Especially if you have leaks on your cannon.

i was thinking since i can't find any kind of fitting to connect to a soda bottle, could i possibly use the weld glue to stick it in a fitting thats just a little big that has threads ? i don't know if I have made myself clear or not

noname wrote:It looks ghetto? I have no idea what you're talking about, that thing is awesome, and looks great. Soda bottles are rated to 160 psi, so you shouldn't have a problem anyway.
Why is the blowgun in that position? Looks kind of awkward to shoot like that.

Soda bottles (sometimes) hold 160psi- they are NOT rated to this.
DWV pipe holds pressure- it is not rated either.

JB weld is worth its weight in gold in certain situations. (Though it costs nearly that- so don't use it on thing you don't have to )

You aren't allowed to call this a 'sniper' until you hit a 5"x5" target at 500 yards, and even that is being generous.

I found that soda bottles (2 liter) burst at an average of 140 psi, it varies depending on age/who made them. With a few layers of duct tape, I've made pneumatics from soda bottles that will hold 160-180 max psi.
I've never been holding a bottle when it burst, but though its not lethal it will probably hurt like hell.

The bottom of the bottle will eventually get distorted by high pressures which might affect the schrader valve seal.

kool. but god knows why u used a ball valve and a sprinkler valve...

imjustpk, very sorry for the late reply. I havn't been at my computer. I filed the old thread off the coke bottle and cut in a new one to match the 3/4 BSP thread. It took a while to do but when I got it, it was completely air tight and very strong.

Mitch.

Sorry for the double post but Ziegs Spud, the ball valve is there purely as a safety measure. I have a couple of dogs and have people around my house all the time. I just didn't want to risk a backfire and a dead dog/lawsuit...

Mitch.

I am a moron. That is all.

Mitchza89 wrote:...I just didn't want to risk a backfire and a dead dog/lawsuit...

Mitch.

What, are you pointing this thing at dogs when your charging it???

judgment_arms wrote:

Mitchza89 wrote:...I just didn't want to risk a backfire and a dead dog/lawsuit...

Mitch.

What, are you pointing this thing at dogs when your charging it???

I pointed my coaxial marble gun in my face when i was charging it to 120 psi

c19o wrote:I pointed my coaxial marble gun in my face when i was charging it to 120 psi

Just because you did something really stupid and got away with it does not mean it's safe, or a good idea for others to do.

I say treat a potato cannon just like a firearm, meaning
1) never point it at anything you're not willing to destroy and take responsibility for destroying
2) keep your finger off the trigger (or sparker or blowgun or whatever) until you're ready to fire AND KNOW WHAT'S BEHIND YOUR TARGET
3) treat it as if it's loaded 24/7 even when you know for a fact that it's not
4) never look down the barrel unless you absolutely must (Such as for cleaning), and open the breech/action or otherwise make it unable to fire before you look in the barrel
5) never joke around with weapons, potato gun or otherwise, it's not funny

Peace,
Pete Zaria.

I know its not safe, I wasnt thinking though. Thanks for the advice, i never thought of " whats behind my target".