Thread: T-Shirt Cannon
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Unread 23-12-2015, 19:18
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Re: T-Shirt Cannon

Quote:
Originally Posted by HumblePie View Post
Here's the result of our offseason project:

We have 4 fixed 3" barrels, all plumbed to a single manifold. The manifold has 3 Clippard tanks plumbed into it, giving approximately 100 cubic inches per shot. Each barrel is plumbed to the manifold through a fairly pricey 1/2" air piloted valve, salvaged from a piece of production equipment slated for disposal at our main sponsor. The manifold is recharged between shots via the compressor and a 2 gallon tank. Manifold refill takes 1.5 to 2 seconds. The ball valves shown are used to precharge the tank and/or manifold with shop air to lessen the load on the compressor (30% duty cycle). Short shots take about 40-50 psi and a full 100 psi charge results in distances of about 90 feet, depending on rolling skill. We use a short section of the barrel material to check the roll, looking for a slight interference fit.
If your Clippard tanks use the usual FRC fitting, those three 1/4" diameter fittings are the limiting factor on getting air to the shirts quickly. If you used a section of galvanized pipe as a tank, with reducers at the end to feed a 3/4" or 1" valve, you could achieve the same launches with much lower pressure and probably less air. 3/4" normally closed valves are available for about $20, and I recall seeing 1" NC valves for less than the 5 port solenoids usually used in FRC.

Edit: This draws more current than the air piloted valve, I am sure. We drive ours through a 12V relay module, though a spike relay could serve the function, if you don't mind driving brads with a 3 pound hammer.

(not that exact module, but a similar one with four ports)
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Last edited by GeeTwo : 23-12-2015 at 19:25.