Quick Answer: The Hand Driven Van De Graaff STEM Lab is a crank-operated electrostatic generator with a 200 mm metal dome on an insulated column, 450 mm high overall. Turning the crank drives a rubber belt that builds static charge on the dome.
Last updated: October 2026
Key Features
Manual hand-crank drive
Polished metal dome, 200 mm diameter
Overall height 450 mm
Rubber belt on an insulated support column
Discharge wand (grounding sphere) with insulated handle and grounding wire
Technical Specifications
Specification
Value
Operation
Manual hand-driven crank
Dome diameter
200 mm (approx. 8 inches)
Overall height
450 mm (approx. 18 inches)
Maximum output
Up to 100,000 volts, varying with humidity
Accessories
Discharge wand with insulated handle and grounding wire
About This Product
Students turn the crank themselves, which ties the mechanical effort to the charge collected on the dome. Classic demonstrations include sparks jumping to the discharge wand, hair standing on end and the repulsion of like charges. It works most reliably in dry air.
Frequently Asked Questions
Why does the Van De Graaff generator not produce sparks?
High humidity is the usual cause, because moisture carries the charge away. Use it in a dry room and check that the rubber belt is clean, unbroken and properly tensioned.
How should the belt and dome be cleaned?
Wipe the dome with a soft, dry cloth. Clean the belt with mild soap and water and let it dry completely before use.
