Materials list. Tap a circle when bought. Tap Buy to open Amazon.
Safety check: standard PVC is not rated for compressed air. At 80-200 PSI it can shatter and throw shrapnel. Fine for low-pressure confetti testing behind a shield. For T-shirt pressures or anything rented to the public, use a rated metal tank for the chamber (see the tank option below) and keep the relief valve in.
How it connects
Engineering plan
Phase 1: Safe bench test (no electronics)
Build the chamber, relief valve, gauge, bleed valve and tire valve first.
Fill to 30 PSI with the barrels removed. Check every joint with soapy water for bubbles.
Wear safety glasses and keep a polycarbonate shield between you and the rig.
Phase 2: Add the valve and one barrel
Plumb chamber, solenoid valve, then one barrel.
Open the valve by hand with a battery or wires to test it fires.
Check the valve opens at low pressure (sprinkler valves can need a minimum PSI).
Phase 3: Confetti tests
Start at 30 PSI, go up 10 PSI at a time.
Log pressure, confetti amount, height and spread for each shot.
Goal: the lowest PSI that gives a good burst. Then try smaller or larger chamber sizes.
Phase 4: Add the wireless trigger
Wire the relay board to the power source and the solenoid.
Pair the key fob. Test range indoors and outdoors (aim for 100+ ft).
Add a fail-safe: relay off means valve closed. Test dead battery behavior.
Phase 5: Two barrels with a tee
Add the tee and second barrel at 45 degrees.
Check both fire evenly and the shots do not collide.
Check the chamber refills fast enough between shots.
Phase 6: Metal tank and higher pressure
Swap the PVC chamber for the rated metal tank before going above low PSI.
Set the relief valve just above your max working pressure.
Only now test T-shirt style loads, shielded and with distance.
Phase 7: Housing and control panel
3D print the bucket-sized housing with a wide, stable base.
Make sure the fill port, gauge and bleed valve are reachable.
Print the master panel for the key fobs or relay board.
Do a tip-over and vibration test.
Phase 8: Repeat and prep for rental
Build 3 units, then 6, and test firing them together from one panel (pair each fob to its unit, or one fob for all).
Write setup, fill and shutdown instructions.
Check liability insurance, venue rules and fire safety before the first paid event.