SpudFiles

Hey everyone,

I just built a pneumatic cannon which is fired using a ball valve. I am currently only shooting water from the cannon because I'm not sure if I will be able to create enough pressure to fire anything else. The most I've fired at was 65 psi, and I'm not even sure if it really fired at that amount: there is a leak between the male threads from the chamber and the ball valve. How do you seal leaks? I've heard of using epoxy, but I don't even know what that is and I don't know the cost.

Any help would be greatly appreciated.

-Vincente

If your spudgun leaks, do not use it, it could come apart and take your hand with it! Just spend the extra $20 to build another one, this time, do not be scringy with glue, use it, that is why you bought it.

for me, my JB Weld cost like 4 bucks, expensive, but it works hella good.

Darkerweb12, it's leaking solvent welds that are bad. Leaking threaded joints are... normal.

There are several meathods;
If you can live with some leakage, go with teflon tape - either the yellow (thick) stuff, or the white stuff.
Use epoxy (you'll be able to find it at walmart, and any hardware store. You should be able to get enough for many projects for 2$ - you don't need the fancy clear stuff, and you don't need [or probably even want] the stuff that cures in 60 seconds or comes with fancy mixing tips. You need to be 17 to buy it, though, so bring an adult) It's often sold atached to a cardboard backing, in a 2-syringe arangment. It's basicaly REALLY good glue, but instead of drying, it undergoes a chemical reaction (no air required, and faster) - a bit like concrete. Just mix it up, apply to those threads, and screw them together. In a few minutes, that arangement will be permenate.
Solvent weld the threaded joints. Just do the same thing that you'd do on normal pipe.