I wrote these plans after building building the project pictured at Lenny R’s Web Page. I drew all of the pictures (excluding the photohraph) using MS Paint. This is a guide on how to make a Leyden Jar that makes awesome blue sparks with materials mostly just lying around your house. It’s cheap, it’s basically harmless, and it’s fun! First, here’s a list of the materials you will need: An empty film canister with its lid Multistrand insulated wire Single conductor/solid uninsulated wire, about 1.5mm in diameter Some aluminum or copper foil (NOTE: Any conductive foil will work. Copper foil is thicker and easier to work with than aluminum foil, Read more »