Interesting. And yes, I am planning on building a epoxy piston valve based on the guide in the how-to forum. It seems like the best way to make a good piston considering I have no machining capabilities. I suppose I will go with long and skinny sch 40 or 80 then because like I don't have any tools t...

I am considering around 300 psi. But I also would like to stick to a cannon type design with a chamber of about 6 inches. Only sch 120 can hold that pressure with that diameter.

I am considering making my second spud gun sometime soon. My first was a rather expensive 8 foot pneumatic with a 2" sprinkler valve. To save cash and space I am thinking about making a short coaxial run at extremely high pressure. I have googled sch 120 and understand that it exists but I have neve...

I think that in a perfect, frictionless system this theory would work out great. But because there is friction it will be many times greater in your coiled system where the projectile will experience a huge force with one side of the pipe (the force that gives it the centripetal motion). So unless y...

Just normal epoxy o both sides of the hole for that right?

I would have liked to use the valve above the main chamber but my diagram doesnt show that there is about a solid inch of angle plastic above it and a vent. I'm not confident I could tap a good hole.

To increase the size of the small hole to the solnoid section I just use a drill right?

Im using a 2" valve sprinkler valve that looks similar to the one below. I plan to add a 3/4" ball valve where the solenoid is because it is conveniently threaded there. The small hole leading from the upper chamber to the solenoid chamber is about 5mm. Is this large enough to be effective or should...

What about a push-button valve then? I don't think they come very large but I've seen a pretty successful cannon use one, http://www.duke.edu/~jwc13/tennisball.html.

So is the whole point of actuating it with another sprinkler valve that it allows for a faster dumping of air so the first valve can open faster? If so is using a second valve that big of a deal because I thought that air can rush through blow valves pretty fast.

Awesome, that definitely makes alot more sense than trying to weld it when its threaded. And one last thing I have heard that for larger valves blow guns don't work that well. Is this true or should a blow gun work fine?

I'm about to start putting together my first cannon ever and I plan to run it at around 125 psi. I've read PC Guys guide to solvent welding on the how to page and found it useful. But my question is, can I just use the normal welding procedure on the joint between my valve and the PVC? Is the plasti...