I first saw a similar launcher at Kyle's site. I call my version the "AA Magnum". I made the drawing not long after I finished the launcher to give spudders an idea of how it was built.. You can also see this drawing at Kyle's site which he was gracious enough to post for me.
I tried to eliminate as much space between the barrel and the chamber, mainly for aesthetics. I made a Sch40 barrel for AA batteries and a Sch80 barrel for 50 cal marbles. The Sch40 launches AA batteries that have been wrapped with about a3" length of 2" wide masking tape. The marbles have O.D. of .500" and the Sch80 barrel has an I.D. of .526", a little big, but not bad (no wadding!). As always, I keep the chamber pressure to a maximum of 100 PSI (I happen to want to keep ALL my body parts!) .
My final version has a barrel with a threaded end so I did not use the male adapter shown here.. I bought a 3-foot piece of regular stand-off pipe which has treaded ends and cut it in half. Also I used a 1/2" steel nipple that I drilled and tapped to 1/8" NPT for the Schrader valve. The nipple is threaded to the chamber. I prefer this method of installing the Schrader valve better than drilling holes into the PVC. I also searched for and found a ball valve that wasn't tight for easier firing.
|
