[Scott] built a confetti canon to spice up the party. It’s pneumatic and re-purposes a fire extinguisher as the air tank. He had a refillable extinguisher that used water instead of chemical retardant. After emptying the water and ensuring all of the pressure had been release he swapped the hose and nozzle for a sprinkler solenoid valve. Securing the extinguisher’s actuator lever with a pipe clamp holds the internal valve open, leaving the solenoid to control the pressure release. This way the canon can be fired electronically, or manually.
This type of solenoid valve is a popular choice with pneumatic canons. We suppose you could even adapt this for use as a T-shirt cannon.
[Thanks BoBeR182]
I wouldnt have thought this kind of solenoid valve would be the best pick given the reaction time delay between trigger and the valve fully opening. This valve works by triggering on a pressure differencial between two sides of a diaphram. The opening time is not that quick I dont think. I could be wrong. A butterfly valve would be my pick.
I’ve built a few air cannons using sprinkler valves. The diaphragm valves sometimes oscillate like a reed in a horn, when triggered. Sounds like a trumpet blast when you fire it. There are sprinkler valves that use a solid piston, rather than a diaphragm. They work a lot better.
Oh this is SO backing up into the mains…
Now if only the guy would invent some way of taking a sequence of photos in rapid succession such that when played back they would give the illusion of real life movement.
With the electric triggering it can cause honking like darus67 mentioned and impede performance. The initial burst of air is quite good and it probably still works better than a butterfly valve would.
These valves can be modified to be triggered by a second smaller valve like the blowguns that are used with an air compressor. This eliminates the need for batteries and gives better performance to the valve. They can open in less than 10ms if properly modified.
@clide
I’m assuming you are the same clide from the Spudtech forums etc? Glad to see another spudgun builder here. I tend to cringe at most pneumatic designs posted on this site. Crappy valves and unrated DWV fittings abound.
You would also get better performance by placing the valve at the base of the actual barrel rather than on the air tank, that way you’re not trying to compress all that air in the hose before you launch your confetti.
I agree with everyone else. You would getter performance if you replaced the confetti with sawdust and an open flame. >:]
powdered coffe creamer works nicely too, make sure you have an ignition source at the opening of the cannon!
*coffee
These valves look promising
http://www.krain.com/electric-valves/proseries-100-electric-valves.html#ScrollToAddToCart
http://www.amazon.com/K-Rain-7001-Electric-Sprinkler-Valve/dp/B001RHIE76/ref=sr_1_11?s=lawn-garden&ie=UTF8&qid=1333186147&sr=1-11