How it works

How it works

A steam engine works by pressure! A fire heats water to make steam. The steam goes up and into a tube and down into a valve. The steam goes through the Valve and straight to the cylinder. The steam pushes the piston back and forth to make the wheels spin and the steam goes up into the air. And then it starts all over again!

Steam line and boiler

Wednesday, March 13, 2013


The first step is to make the valve because that is the hardest part.

1. Cut a hole in the side of a straw but not too big.

2. Put some hot glue around the hole but not in it!

3.Stick a short piece of bendy straw over the hole. Put some glue
around the hole to seal it because the engine will not work if air

4. Straighten a paper clip to make the valve stem.

5. Cut a small circle out of a small piece of plastic for the valve plug. It should just fit in the straw. Make a hole in the middle for the stem.

6. Glue the circle to the end of the stem.

7. Cut a circle of soft material that is a little bigger than the plastic circle. The woven side of a face cleaning pad works well.

8. Glue this to the plastic circle.

9. Glue the paper clip in the end of a straw.

10. Make a hole in the other end of the straw. This will go on the crankshaft.

11. Now the valve is done! Try it by blowing in the end and sliding the plug up and down. It should not leak much when it is closed. If it leaks try step 7 again with a bigger circle of material.


  1. hello ı try try but ı dont work it ..please help

    1. Is the valve not sealing tightly? Try making the plastic disk or the fabric seal wider. It has to be a really close fit. If your straw is the right diameter you can also try a cotton swab instead off the disk. If the disk is getting stuck on the edges of the hole in the side, try making the hole a bit smaller or making sure the edges flare outward slightly. Let me know if I can help with anything else.

  2. I dont understand some issues.Will the air in the balloon same level ? when I blow into balloon and sit in plastic tube ,system didnt work it and balloon blow out in the time ..may I send a photo my system and tell you what ı did wrong ?

  3. It sounds as though your valve may not be positioned correctly. Let's see the picture, maybe that will help show where the problem is.