HV Supply DC or AC
Piece of stiff Card
Cover the card with the aluminium foil and cut out into a rotor shape. Find the center of the rotor and make an indentation in the car with the needle. Balance the rotor on a needle pushed into the cork. Attach one side of the HV supply to the needle and the other to earth.
If a small DC power supply is used, a small rotor can be made 50mm or so in diameter.
If a Tesla coil is used then you will need a larger rotor, Up to 300mm can be made with the method above. If you have a bigger tesla coil then make a larger rotor from copper tubing balanced on a needle point.
Switching on the supply causes the rotor to spin. If the rotor doesn’t spin, move an earthed object nearer the rotor. For the rotor to spin, the bearing must allow the rotor to spin freely, Ensure the needle hasn’t gone too far through the card. The card should just rest on the end of the needle. If the needle has broken through the card the rotor will not spin freely enough.