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Unread 01-11-2011, 19:12
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Travis Hoffman Travis Hoffman is offline
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FRC #0048 (Delphi E.L.I.T.E.)
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Re: Over-engineered T-Shirt Cannon

Quote:
Originally Posted by EricH View Post
Not necessarily.

You could lock down around the belt.
You could build a belt that looks like _O_O_O_O_O_O_O_O_, where the O signifies a "cartridge" that has seals on the ends and a rolled-up T-shirt in the middle. That's the basic premise behind Shockwave's revolver section maintaining most of its pressure, IIRC.
You could fire at extra-high pressure. That's a bit risky, though.
To my knowledge, Shockwave has no seals anywhere in its cannon assembly - its rotating barrel carrier (powder coated aluminum) butts up against the fixed rear of the cannon (lexan), and this interface maintains a very small gap (1/32" or so, if I recall) during barrel rotation and cannon firing. This small gap limits the amount of air leakage at that interface during firing. It is a very simple system and works very well.

I have no idea why I'd know all of these details offhand.
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