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How to Make a Van de Graaff

A Van de Graaff generator uses the principles of electromagnetism to generate a static electrical charge. Robert J. Van de Graaff first designed the hair-raising sphere while he was a professor at MIT in the 1930s. Originally, Van de Graaff built huge generators, capable of generating up to 1 million volts of electricity. He used them in atomic experiments. Today, the generators are primarily used is school demonstrations. The generator is easy to build with items found around the house or the hardware store.

Things You'll Need

3-inch diameter PVC pipe, 2-feet long
Drill
1-inch bit
1/4-inch bit
2-inch paint rollers
Rubber resistance band
Vacuum cleaner belt
2 wire coat hangers
Scissors
Epoxy
Document clips
3-inch PVC collar
1/2-inch wood screws
2-foot by-2-foot plywood, 1-inch thick
3 mil copper sheeting
PVC cement
Electrical tape
Soda can

Instructions

- 1
  Drill a 1-inch hole 2 inches from one end of the PVC pipe. Rotate the pipe one-quarter turn and drill a 1/4-inch hole all the way through both side of the pipe. Drill a second 1/4-inch pipe through the other end of the pipe directly above the first two holes.
- 2
  Pull both paint rollers from their handles. Wrap the rubber resistance band and the vacuum cleaner belt around one roller. Insert the coat hanger through one of the 1/4-inch holes near the 1-inch hole. Thread the wire through the roller with the bands and out through the other side of the pipe. Bend the coat hanger to hold it in place. Turn the pipe so that the resistance band falls out the other end. Slip the second roller inside the loop of the resistance band. Hold the roller in place while you secure the second roller with the second coat hanger.
- 3
  Pull the resistance band so that the band is taut, but not tight. Cut off the excess band with scissors, holding on to both sides firmly. Spread epoxy on both sides of the band and hold the ends of the band together with the document clips until the epoxy dries. Leave it overnight.
- 4
  Cut two 1-inch pieces of copper sheet. Cut fringes along one side of both squares.
- 5
  Screw the PVC collar onto one end of the wooden board. Punch a hole through the solid side of one copper square and screw it to the wood in the center of the PVC collar.
- 6
  Push the vacuum cleaner belt out of the PVC tube through the 1-inch hole. Spread the PVC cement around the inside of the PVC collar. Place the pipe with the belt sticking out on the bottom. Let the cent dry for 2 hours.
- 7
  Hold the second fringed copper square over the center top of the PVC pipe. The fringed side of the square must be long enough to be near, but not touch the rubber resistance band. Tape the solid end of the copper square to the hole in the soda can. Tape the soda can to the top of the PVC pipe.
- 8
  Look through the 1-nch hole to check the placement of the other copper square. Make sure that the copper fringe is close to, but not touching the rubber resistance band.
- 9
  Remove the drill bit from the drill. Wrap the vacuum cleaner belt around the turning head of the drill. Pull so that the belt is taut.
- 10
  Turn on the drill. The rotating drill turns the bottom roller with the belt. The belt acts as a pulley and rotates the upper roller. The copper fringe picks up the charged particles and spreads them out over the metal soda can.

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