Air driven prop

Hello,<br /><br />I want to use air from a scuba tank to drive a prop.<br />I can find no info on this on the Web. I do remember seeing a guy who got attacked by a shark who developed a personal shark cage that motored around with what seemed to be air driven propellers.<br />As a starting point of thought I was thinking Air tool + shaft + prop + welder and bingo. Could this work?<br /><br />H90

Re: Air driven prop

No. It would run for maybe a minute before you run out of air. Not to mention it would be extremely slow on any type of boat.

Re: Air driven prop

who said I was gonna use it on a boat...........

Re: Air driven prop

What are you using it in? Even in a model boat it wouldn't last for more than a minute or two...

Re: Air driven prop

There are (used to be?) a couple manufactures of underwater scooters powered by steel-72’s. The 72 is preferred over the al-80 because of buoyancy characteristic. One company was making an al-80 unit that would propel and you could breath off the same tank while tooling around. In an application like this, buoyancy at depletion may not be a bad thing, if you want to keep your scooter. <br /><br />Given the endless array of pneumatic paraphernalia that is now available, I would think building a scooter wouldn’t be that difficult. Propeller-size choice would be a stumper for me. Get your hands on an industrial catalog, something you can page thru and look at gismos for idea and compare specs. Try www.mscdirect.com ‘s Big Book. It’s free and arrives USP in a couple of days. Grainer has a free catalog also, but not as big. It’s a start. I think what you are after is called an “air motor” or pneumatic motor. <br /><br />Don’t know what you need but comparing a couple air motors, <br /><br />2000rpm – 0.1hp – 6cfm of air at 20psi - $127.00<br /> 300rpm – 0.1hp – 20cfm of air at 20psi - $389.00<br /><br />Some local guy built an electric unit, strapped the battery to his chest and had his tank on his back. While tooling around with his scooter he came across Fluffy and chased her. Initially Fluffy went away, then stopped, turn, and came back and bit the guy. Fluffy chomped down on the tank and up on the battery…that’s how big Fluffy was, one bite. They guy laughs and said he felt some pressure but otherwise, being attacked by a great white shark is no big deal. I’m not sure chasing Fluffy was a good idea…it’s Darwinian, his days a numbered.<br /><br />I don’t even know if this is the application you had in mind…chasing Fluffy.

Re: Air driven prop

That is along the lines I was thinking. Also a setup to blow sand of the the bottom while using an under water metal detector. Limited use while diveng in lakes. Thanks or the tip on the catalog.