Thread: T-Shirt Cannon
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Unread 28-12-2015, 07:35
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Re: T-Shirt Cannon

[quote=GeeTwo;1514515]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.

Thanks for the input.

Since this was being built from mostly scavenged parts, and didn't have to be FRC legal, we prototyped a single cannon with the 1/2" valves we had available and a commercially available (small) manifold with 4 Clippard tanks attached. Initial trials were uninspiring. Your point about cross-sectional flow area is well taken, as when we opened up the ports on the Clippard tanks to 3/8"NPT, we were shooting about 90 feet at 100psi. We were even able to maintain that distance with just 3 accumulator tanks, so that's where the design is now. We also replaced some tube fittings between the manifold with a 1/2" close nipple to improve flow. Down the road, we'll see about replacing one of the Clippard tanks with a smaller one and see if we can maintain a similar (or at least acceptable) max distance.

Can't wait for January 9th!
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