I thought it'd be cool to make a mini confetti cannon that could be charged and fired electronically. Does anyone know how to build and release air pressure using electronic components? I'm assuming releasing air pressure (firing a confetti cannon) would involve some kind of switchable valve, but I haven't a clue how to do air pressure without a bicycle pump let alone with an Arduino kit.
there are some options already designed dunno if i can link to other sites but if you google it they come up
This is an okay resource for the basic construction of a mechanical one http://www.handheldconfetticannon.com/
would involve some kind of switchable valve
It's called a [u]solenoid valve[/u]. The bad news is they are expensive. The online manual version uses a 1/2-inch valve. A bigger pipe & valve allows more air to flow.... You don't want a "leak" you want a big blast of air, so I wouldn't go any smaller than 1/2 inch.
You'll need a [u]driver circuit[/u] to run the solenoid valve from the Arduino.
but I haven't a clue how to do air pressure without a bicycle pump let alone with an Arduino kit.
It's called an [u]air compressor[/u]. You don't need a "big one" with a lot of continuous air-flow (CFM) because you just need a quick blast, but you do need the air pressure (PSI). Compressors automatically shut-off when the tank is fully-pressurized so the compressor doesn't need a connection to the Arduino.
It's called a solenoid valve. The bad news is they are expensive.
Adafruit has them pretty cheap ;D
Plastic Water Solenoid Valve - 12V - 1/2" Nominal
EDIT: FYI the manual valve shown in the video is also a "water" valve
A said you need a wide bore valve a solenoid valve has only a small orifice.
Manual ball valves are affordable and work but the problem is opening them fast enough electricaly.
Air escapes pretty easily unless you use a really small orifice. I've used that type of solenoid valve for a tennis ball launcher 
confetti will not be a problem
DVDdoug:
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"The extreme party popper by Craig Turner"
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