Orange | Our Globes Outdoor Sports

Orange Mini

March 5th, 2010 admin No comments

Orange Mini

how can I create a fast mini boat motor?

For a school project i need to create a marine device that carries an orange around our school fountain... I have chosen to make somewhat of a mini boat. I will use foam to create a rectangular body and I will cut in a square space to place the motor. The back of the body will have an outlet for the propellers. I know the design will work, I just don't know how to make a fast and efficiant motor. can anyone please help?

Like mike says, making an electric motor would be challenging. Easier to construct : A steam engine, like the first one made by hero of Alexander?

http://en.wikipedia.org/wiki/Hero_of_Alexandria

You could make the boiler out of a tin can, with a 1/2" copper pipe run through it. Drill a hole in the copper pipe for the steam to exit the can. Using solder and a propane torch, solder fittings to the pipe, so that you end up with a couple arms sticking out. You'll also need to seal the pipe where it goes thru the ends of the can - it'll probably solder OK. If not, you may have to use sealer. A plumber could show you how to solder. You'll want to nozzle the outlets, smaller holes for higher speed. Add paddles?

You could heat the boiler with a "smudge pot" type burner. This would be a tuna can with some rubbing alcohol (or gas), and a wadded up paper towel for a wick. The wick won't burn away as long as it's wet with alcohol.

You won't get very high pressure (and speed) out of it without bursting the can, so you won't be able to have very small nozzles. It's dubious if you will get enough propulsion out of a high volume of low pressure steam, it'll take some experimenting. maybe insulating the top of the can boiler with a tin sheild will help keep heat in (like a double walled stovepipe)

Wear safety glasses and stay far away from it until you're sure it's all cooled off and depressurized. you could test your burner and boiler by setting it up on the ground, with a long wire attached so you could pull the burner out from under. That way you could test different nozzle sizes - just squeeze the pipe ends more or less.

For the hull - how about a couple of plastic two liter bottles? put a board between them, screw each bottle to the board. if the board extends down a bit, it will act like a "keel" and keep the boat going straight. You could make it go around by holding onto a string, and walking around the opposite side of the fountain? Drill a hole in the board, and it will act as one of the two "bearings" for your motor. Put the orange in one side, and the burner/ boiler in the other.

That still sounds like a very ambitious school project. Maybe your teacher is thinking more along the lines of a rubber band motor? You can get corks with holes at a hardware store, have a loose fitting shaft (threaded hanger loop) and balance your orange so that the shaft is above water.

Or you could use the boiler, and expel the steam through a small tube, inside of a larger tube mounted underwater. The steam would "draw" along a larger amount of water, probably more efficient and compact and easier to build - a "venturi effect" water jet drive. Generate pressure with soda and vinegar ? Or dry ice- careful, you can explode a sealed bottle HARD, Lots of pressure that way, but as long as theres a good outlet....