The expression "steam engine" refers to the 19th century with the manufacture of the first locomotives or the first steam cars (Stanley Steamer). Be aware, however, that they were not only used to move land vehicles faster. The very principle of the steam engine goes back to Antiquity with the machine of Heron of Alexandria, that is to say more than 2000 years! For three centuries, these steam engines have supplied and still supply (together with the turbines of the power stations) 80% of all the electrical energy consumed in the world today. If you want to better understand the main principles, we invite you to make some simple steam engines using materials and tools that anyone can own at home.
Method 1 of 2: Using a can of soda (for kids)
Step 1. Cut a can to a height of 6.5 cm from the bottom
Using tin snips or a sturdy pair of scissors, cut away the bobbin to keep only the bottom third.
Step 2. Using a pair of pliers, fold the sharp and uneven edges inward and flatten them well
The goal is to prevent you from hurting yourself. Be careful not to injure yourself during this operation!
Step 3. Push back the domed part of the bobbin to get a flat bottom
As you have already noticed, these cans have a circular bottom that is slightly domed inwards. You can push it back by hand or with the help of a small glass (or a small bottle) with which you will have more force.
Step 4. Drill two small holes opposite each other about 1.5cm from the top
You can use a paper puncher or a somewhat large nail and hammer. The holes should be about 3mm in diameter.
Step 5. Place a candle in the middle of the can
Crumple some aluminum foil and place it under and around your tealight to stabilize it. The candles are poured into small tin cylinders, so there is no risk of wax coming out.
Step 6. Wind the central part of a copper tube (15-20 cm long and 3 mm in diameter) around a pencil
Make two or three turns around the pencil. The section of the tube being small, the winding will be done without difficulty. This "spiral" should be the width of the bobbin and you should have about 5cm of straight tube left on each side.
Step 7. Insert the ends of the tubes into the holes in the bobbin
Center the spiral over the tealight wick. On each side of the can, you should have two identical lengths of tubing.
Step 8. Bend both ends of the tubes at right angles
If you bend one end to the right, you will bend the other to the left, with the tube remaining in the same plane. Finally, fold these angled parts again so that the ends are below the bottom of the bobbin. In the end, you should have a spiral part above the candle and two double bent sections on either side.
Step 9. Place your can so equipped in a large container filled with water
Place your can on the water and make sure the ends of the tubes are in the water. Normally your "machine" should be stable. If the tubes do not sink well into the water, apply a little pressure on your installation, but be careful that it does not sink from the bottom!
Step 10. Fill the tubes with water
The easiest way is to immerse one end in a container filled with water and vacuum through the other end, like a straw. You can also plug the bottom opening with a finger and fill from the top under a stream of tap water.
Step 11. Light the candle
The water in the tubes will heat up and then start to boil. The steam thus generated will come out of the tubes in the form of "jets", which will cause the rotation of your machine.
Method 2 of 2: Use a paint bucket (for adults)
Step 1. Cut a 15 x 5 cm rectangular hole on one side of the pot, quite close to the base
This rectangle will be in the horizontal direction (the 15 cm will be measured parallel to your table).
Only take jars that have contained latex (or vinyl) paint that you have taken care to wash well with water and detergent
Step 2. Cut a piece of 12 by 24 cm from the wire mesh
Fold at a right angle (90 °) 6 cm on each side of the long length. You thus obtain a sort of square “platform” measuring 12 by 12 cm, with two “supports” 6 cm high. Place this trellis in the paint bucket, feet facing down and aligned with the edges of the hole you cut. The space behind the hole is left free, this is where you will light the charcoal which is on the trellis.
Step 3. Make ventilation holes on the cover
You will need to burn charcoal to run your steam engine. If you don't have an air supply, your charcoal will burn badly or not at all. To ensure good ventilation, drill a series of small holes on the edge of the cover, on one half of the perimeter.
These ventilation holes will be 1 cm in diameter
Step 4. Make a spiral with the copper tube
Take a flexible copper tube 6 meters long and about 6 mm in section. Measure 30cm from one end. From there, make 5 spirals 12 cm in diameter. Next, make 15 smaller spirals 8 cm in diameter. You should have about eight inches of tube left at the other end.
Step 5. Insert the ends of the spiral into the ventilation holes in the cover
Fold the two ends of the spiral upwards, as in the picture. If you don't have enough length, undo one of the spirals.
Step 6. Install the spiral and charcoal in the pot
Place the spiral on the wire mesh. Fill in the space around with pieces of charcoal. Close everything tightly with the lid.
Step 7. To route the plastic pipes, drill holes in the small paint can
In the center of the lid of this liter jar, drill a hole one centimeter in diameter. On the side of the pot, also drill two one-centimeter holes, one near the bottom and another near the lid.
Step 8. Install two small plastic pipes on the upper small pot
Take or cut two small corks that will go by forcing a little into the two small holes. Insert in each of them a small rigid plastic pipe, one will be 25 cm long and will be placed on the bottom hole, the other will be 10 cm long and will be on the top hole. Secure the plastic pipes (which pass right through the stopper) in the stopper using small clamps.
Step 9. Connect the two paint cans together
Place the small pot on the big one, the holes of the small one should not be above the ventilation holes of the big one. The plastic tubing from the bottom of the small pot should be secured to the copper end that runs from the bottom of the spiral. The other plastic pipe is attached to the other copper end. At the junctions, put metal adhesive so that the "weld" is waterproof.
Step 10. Insert the copper tube into the junction box
Using a hammer and screwdriver, remove the central part of a metal junction or junction box. The latter must have a fixed tie-down collar inside. Pass a small copper pipe 15 cm long through this collar, your pipe should protrude a few centimeters above the top of the junction box. With a hammer, slightly round the edges of this protruding end. With the junction box placed upside down (hollow part facing down) on the small paint can, push the small copper pipe into the central hole in the lid of the small pot. Tighten the clamp so that the copper pipe does not move.
Step 11. Insert a skewer into a wooden cylinder
Take a thin wooden barbecue skewer and insert it into a hollow wooden cylinder 9mm in diameter and 1.5cm in length. Slide this skewer-wood cylinder assembly into the copper pipe of the junction box, skewer facing up. The rounded edges of the copper pipe will prevent the wood cylinder from coming out upwards.
The wooden skewer-cylinder assembly will act as a "piston". If you want to observe its movements, you can put a small paper “flag” at the top
Step 12. Prepare your steamer
Remove the junction box and fill the upper small pot. The water will gradually flow into the copper spiral, which will be filled when the small pot is two-thirds full. See if there are any leaks and if everything is properly closed. Replace the lids and push them in firmly with a hammer (do not hit too hard anyway!) Put the junction box in its place, i.e. above the upper small pot.
Step 13. And let's go for the experience
Poke newspaper into the rectangular hole under the wire mesh. Do not pack the newspaper too tightly. Once the fire is gone, let it burn for 20-30 minutes. The water will start to boil and steam will form in the upper container. When the pressure is sufficient, it will push the piston upwards. When the pressure drops as a result of the steam leak, the piston will fall back on its own by gravity. If necessary, trim the length of the skewer. Indeed, the lighter it will be, the more often it will move. Ideally, this piston should be lightened so that your little flag has regular vertical movements. You have to go through trial and error to find the right weight of what you might call a pressure regulator.
To improve combustion, you can use a hair dryer that you direct to the ventilation holes
Step 14. Be careful
It goes without saying that such an experience is not without its dangers. Handle with care. Indulge in this experience outdoors. Do not stand near potentially flammable materials, such as dry leaves or under a tree! Place your machine on a safe surface, such as a concrete floor. If you are surrounded by children, take all necessary precautions. Never leave them alone with your machine, especially if it is running. Be careful not to touch anything: the burns can be very severe!
You must absolutely make sure that the steam escapes well from the upper “boiler”. If the piston were to get stuck, the steam would concentrate in the small container until it reached a very high pressure. You risk an explosion, you can easily imagine the consequences if you are nearby. So be careful …
Install your steam engine on a miniature plastic boat. One of the tubes should be submerged in water and the other should serve as the steam exhaust. To be in tune with the times, do some recovery, trim your boat in a large plastic bottle of soda or detergent
- If you need to handle your machine while it is in operation, use pliers or a pot holder. Don't go with your bare hands!
- If you are not sure you have it right, do not try to build a more complex machine, with a larger boiler for example. Even a small boiler explosion could have serious consequences.
- If you should handle your steamer while it is in operation, be careful not to point the copper tubes in the direction of anyone, the steam coming out of it is very hot.
- Under no circumstances should you artificially plug the copper pipes. The tips should just be underwater. If you plug them, the pipes will explode with the consequences you imagine.