400mm Van De Graff kit Safety, Tips, Maintenance and Cleaning


The van de Graff  must have an Earth connected to the bottom brass comb, this can be provided from any large metal object, radiators, table tops. Do Not connect this to any part of mains wiring.

Keep away from all other electronics ! – 180,000 volts can kill electronic items, keep your VDG away from anything electrical or electronic.

For best results

The brass combs need to be close, but not touching the belt in operation. It is easiest to set this when the VDG is running slowly. Remember that there is a joint in the belt that is slightly thicker than the rest of the belt and this will have to pass the combs. If the belt is showing scuff lines on the outside, it  is most likely that one of the combs is rubbing on the belt.

The Van de Graaff will run best when clean and dry. It will also run better in cold dry weather.

In dry weather when everything is clean your Van de Graaff kit should be capable of 60mm sparks or better.

If the belt is worn, chaffed or you are unable to clean the belt replace it.

If the atmosphere or your kit becomes damp it will stop working, try drying the kit with a hair dryer and cleaning the kit as detailed below.

If the output is poor and this can be improved by gently rubbing a dry cloth onto the belt. If that doesn’t improve output, it is likely that your rollers or belt need cleaning or replacing, or the humidity is too high. You can check your local humidity levels at Weather.com or by purchasing a humidity meter . If the relative humidity (in the room) is greater than 50% then you may experience problems with the VDG charging .


If your Van De Graff fails to run or has poor output. Try carefully cleaning the belt with pure soap and leaving to dry, clean the rollers with IPA if possible and/or dry with a hair dryer.

Do not use any oil, polish, or anything that will leave a residue on the belt or rollers.

The motor will run from 6V to 12V, but takes 0.5 to 1A a good battery or power supply is recommended. Avoid using Electronic power supplies.

If the elastic bands get dirty you can wash them in plain soap or washing up liquid. Rince them thoroughly with clean water and don’t use them until they are absolutely dry. The Van De Graff column and rollers can be cleaned with a good screen wipe or lens cleaner, but not one that leaves any form of residue, don’t use baby wipes.

If the motor or belt doesn’t turn, first check the batteries, and make sure the rollers are fee to turn, if the belt is worn replace it.

Do not lubricate any part of the Van de Graaff, The charging works by direct contact between two dissimilar materials. If there is a layer of oil, however small, on the belt or rollers this contact doesn’t happen, and the VDG won’t operate.

If your rollers or belt no longer charge at all, consider getting a new set with our maintanance kit (coming soon)