Last week, I had an epiphany working in my lab. We use stopcocks in our small setups all the time, I had just never thought about adapting them for Nerf. In case you didn't know, a stopc-ck allows you to line up any 2 OR 3 lines off of it, with one side sealed off. It also means that, for Nerfing purposes, any of the three sides can be your air input, not just the middle hole. It's also extremely easy to make, as it turns out.
.5" CPVC tee
Hot glue/solvent weld (Hot glue seems strong enough, though)
Cut out 1" lengths of both PVC sizes. They should fit into one another with a bit of wiggle room to spare, right? If not, you need to check your PVC again and make sure you have the right diameters. Anyhow, cut craft foam to the needed width and length to wrap around the inside of the 2" PVC. Spread your goop very evenly around the inside of your 2" PVC, and put your craft foam in place. Now put the 1.5" PVC inside the craft foam (NOT glued to it, mind you) to compress it and hold it in place. Let it cure.
After everything is dry, take your pieces and drill 5/8" holes at the 0, 90, and 180 degree positions. Remove shavings, and then remove your 1.5" PVC piece. Cut down the CPVC tee until it fits inside, and then glue/solvent weld in place.
And that is it, you have an airtight stopcock! You can add a handle of your choice to it to let you turn it easier, and you can make flat pieces to cover either side of the stopcock. Although to keep with standards, I'd suggest having the handle arm face the direction without a hole; much easier on your head.
Feel free to glue/solvent weld PVC around the rim as needed for your particular situation.
Edited by Buffdaddy, 17 August 2010 - 11:27 AM.