SpudFiles

well here goes for my first post:

i have lots of 2" PVC lying around the house. I want to build an "inline" pneumatic launcher. what length do suggest i make the chamber? i'm going to use 1.5" PVC for the barrel. I used 2 lengths of 2" PVC 18" long to make a "confetti" launcher for my wife. we used it on a float to launch shredded pom pom bits into the air. i only put 20lbs of pressure each time and it worked pretty good.

i used a 1" rain bird valve and i'm going to use the same valve (now modified) for my inline launcher. am i wasting my time with the 2" PVC? should i go out and get 3" or 4" PVC? also i know that some fittings aren't pressure rated. what are the markings i should be looking for? thanks in advance for any help.


phirst

The PVC you plan to use should say its pressure-wrated or has NSF-PW on it Try to find the stuff that cleary has NSF-PW on it.

Generaly, a sprinkler valve doesn't have enough flow to effectivly launch projectiles out of 3" or larger bores - velocity tends to max out due to the flow restriction.
Model it with the GGDT, if you want to see for sure.

LJR - thanks for the info. i will make sure it is pressure rated. i have seen both and the differences are clearly marked. the 2" pvc i have is pressure reated for 280psi. What type of markings should i be looking for on the fittings?

boilingleadbath - thanks for the valve info. unfortunately the 1" valves are the biggest ones i can find w/o ordering online and i don't want to do that if i can avoid it. The barrel i plan to use is only 1.5" anyways.

ok back to my orig question. Will a 2" chamber be sufficient or should i go w/a 3" or 4" chamber? and if the 2" is ok to use what size length should the chamber be? i can get bigger sizes PVC but it gets way more expensive. Oh yeah, i plan on using the shraeder valves with the NPT male fitting on the end. do they sell those at auto parts stores?

Thanks for the help w/all my questions.

Phirst