The amazing pringles Stirling engine, made from cardboard Pringles tube. When I saw this video by MarekSHayward I just had to have my own! It impressed me seeing a Stirling engine made mostly out of cardboard, something which wouldn't normally be workable in an external combustion engine. This is a really easy to build Stirling that should be accessible to almost anyone.
How does it work ?
This engine uses air which is repeated heated and cooled. To allow the air to be heated and cooled the pringles tube contains a displacer which is like a loose piston that can move up and down forcing the air around the engine. When the air is heated it expands pushing the diaphragm (balloon) outward which turns the cranks. When the cranks turn they move the displacer down so that the air is near the top where it is cooled causing it to shrink and pull the cranks back, which of course moves the displacer upwards allowing the air to be heated at the bottom, this repeats over and over!
4 x Pringles tubes, clean and dry
1 x Balloon
1 x Air freshener lid/ small aerosol lid
Cardboard from an old shipping box
Several plastic straws
General purpose adhesive
Hot melt glue
Fishing line (the creator of the original engine used cotton thread instead)