Update:
1. The slide valve worked very well, but newbies had trouble with it. So, I modified a blow gun for the pilot and added a push button for the pressure chamber fill.
2. Standard plumbing replaced with a custom machined manifold on the pilot side of the QEV. It integrates the blow gun pilot, gauge, fill valve and pistol grip mount into one piece of steel. I turned it down, bored a .335 hole and drilled tapped 1/4 & 1/8 pipe thread holes for the various components. I cut 3/4 pipe threads on one end and machined flat spots on the other end to get a wrench on it.
3. Standard 1" scope rings work pretty good for mounting the Palmer female stabilizer. The ring was welded onto the bottom of my custom made pistol grip. Really, there's no better way to mount the reg as the 1/8 pipe threads aren't substantial enough.
4. Custom pistol grip. Made from 1 1/4 EMT, flattened to an oval in a press and welded to a split 1" pipe half. It's bolted to the custom manifold. A 1/4" 800psi plastic hose from Palmer makes the connection from the reg to the manifold.
5. I added an adjustable pressure relief valve from Palmer to the FS reg. I also added a push button bleed valve to the elbow of the pressure chamber. So, the launcher can be discharged safely if you don't want to fire it.
6. Added a pressure snubber to the pressure gauge to protect it from the sudden pressure drop when fired.
7. Custom pressure chamber. I welded this from 1 1/4" galvanized pipe and a 3/4" nipple. After blending the welds, I hydro tested it with my hydraulic press to 700psi. I even stamped the end cap with the pressure rating and date.
8. I covered the welds up on my barrels with bondo and sanded them down while spinning them on the lathe. Made for a nice look.
Overall the gun is nicely balanced and the ergonomics are comfortable. It is heavy at 11.5 lb (including the 48ci HPA tank which weighs 3lb). Just about anyone can shoot it with minimal instructions. You can fill the pressure chamber at whatever pressure you want for each individual launch which is nice. The reg is set for 250psi so it keeps anyone from filling it to some crazy pressure. At 200psi, I'm shooting 120' with a nice arc. That's probably about right for most t-shirt launching in medium size football fields. Some more testing and then some final paint... And perhaps, a custom foam case layout using my hot wire foam cutting table...we'll see.
MOAR DAMAGE!!!
