My model has methylated spirits burner under the boiler. The boiler has a metal tube that comes out of the topside of the boiler. When the water in the boiler boils the steam comes out the metal tube and turns the turbine blades inside the paddle-steamer that turns the shaft and the shaft turns the paddles.

When I made my model one of the difficult things was getting the materials I need to make my model. The first thing I did was make the boiler and test different ways of boiling the water. The way I tried first was a little candle from an incense burner but it did not work so I tried a methylated spirit burner from Dad's camping stove and it worked fine. Next I got the wood and marked the cutting lines and used Dad's jigsaw to cut the wood and the cement sheet. Next I cut holes in the side of the wood for the shaft and the bearings. Then I glued and nailed it together

The scientific principle of my model is:

When water in the boiler turns to steam it expands and creates pressure inside the boiler. The pressure forces the steam out the tube and turns the turbine blades.

One of the problems I had was that I made a turbine blade out of a balsa wood with a thick wood shaft but it did not work. Next I tried a turbine blade made from a tin can on a wooden shaft but it only just worked. Next I tried the same turbine blade with a thinner metal shaft and this time it span easily.

On a previous boiler it was hard to get water into the boiler because the hole is so small. I over came this problem by taking the boiler straight out of the paddle-steamer while it was hot and putting it in cold water. Because when the boiler is hot, cold water makes it contract causing it to suck in water and refilling the boiler. But that was a difficult system and it lead to another problem of rust. Because the boiler was always full of water it rusted out. I overcame this problem by getting Dad's friend to solder a drain plug in so it was easy to fill and drain the boiler. After draining I put in some cooking oil.

The main improvement I could have made is that the shaft I used bent very easily. I only used it because it worked a lot better than the other shaft.

The paddle of the paddle-steamer only goes in one direction to keep it simple. An improvement I could have made is to have two boilers and two turbine blades. One boiler turning one turbine clockwise and the other turbine turning anti-clockwise, therefore having backward and forward movement.

Another improvement I could have made is to have a valve and an extra pipe to redirect the steam and to make the turbine blade be able to go two directions.

The rubber bands are on the nail to use as a drive belt in case I want to put in a generator in future. One possible use of a generator would be to have it power a fan that sucks in air to give the fire more oxygen to keep the burner alight.

Andrew Burke

1999