A few questions EDIT:New question

[semme]

Hi I am new to this forum. My friends and I are building an air cannon for physics class and have a design but still have a question or two. We are going to use a sprinkler valve. Anyone have any good suggestions for ones? and also how do you rig up the circuit to set it off? Thats the only question that we have now so thanks in advance. We should have pictures in a few days as we start building saturday.

Edit::
Thanks for helping and we have decided to get a sprinkler valve and mod it. Also how do you get a shrader valve in the PVC and where would you recommend putting it? Do you just drill a hole or what? Thanks for the help.

[SpudStuff]

I would reccomend a orbit watermaster jartop. Don't mess around with a electrical system, modify the valve with a small ball valve as seen here
This might help you with any calculation you might have to do.

Also make sure ALL the fittings and pipe say NSF-PW on them.

[semme]

Thanks man.