Ensure that the 4 brushes are lightly touching the foil sectors on the discs and that they are free to rotate.
Set the two balls to be about 5mm apart.
Put in a new set of 4 x AA cells and turn on the Wimshurst machine.
Both discs should rotate in opposite directions.
If the machine doesn’t work, please take a look at the tips below.
Although the voltages produced by product are safe for humans, this is not true for any other electronic device. IT MUST NOT BE USED WITHIN 300mm OF ANY ELECTRONIC EQUIPMENT. Also be aware whilst using the device you may pick up electrostatic charge, do not operate any electronics whilst using the device. You are a conductor.
Tips (a work in progress)
In hot humid conditions your Wimshurst may stop working (or not work at all) use a hair dryer (on a medium heat) to remove the humidity from the air/Wimshurst machine.
You can help to start the Wimshurst machine, by running the disks and inserting a clean kitchen towel between them for a short while. As soon as the sparks start, you can remove the towel and the machine will continue to generate voltage.
Keep it clean
Your Wimshurst will only work if the disks, sides and capacitors are clean. Use an isopropyl alcohol cleaner.