I have a huge costume party every year. The inside of my home is pretty much transformed into a mini haunted house. The main theme I want to focus on is like a Hazmat Zombie Wasteland area that guests have to walk through. I have 55 gallon drums, buckets, lights, fog machines. What other props...
I bought a real air valve for my air cannon (don't use a sprinkler valve) to fix the problem and placed it in a biohazard barrel.
It is lot louder in real life than it seems in the video.
YouTube - Biohazard Air Cannon
Here is my completed Biohazard barrel with all the pneumatic guts installed. The action is slower than I would like and I have 100 psi on the cylinder. I hope I can speed it up a bit.
YouTube - Biohazard Barrel Complete - Pneumatic Halloween Prop