Michael, Elizabeth, and I made a table-top sized Van de Graaff generator.
Step 1: Materials
This is what you need:
• 1' long 4" diameter PVC tube
• 5" long section of 1/2" CPVC pipe
• 1 airplane blanket (or other static material like rubber of fleece)
• Metal Bowls
• Scraps of 2x4
• Dowel (lots of dowel)
• JB Weld (I now love this stuff)
• Hot Glue
• *Optional* a ball bearing for shoving in a hole
Also, 2 friends insane enough to do this with you!
Step 2: Cut and Drill
Sorry for the bullets, but there are some pretty simple steps to be done:
• Cut a hole in the bottom of one of the bowls to make room for the wire brushes
• Drill a hole in the PVC tube large enough to fit the CPVC through
• Route of drill a hole in the 2x4 to make room for the dowel to spin
• Drill the straightest possible hole in the dowel to put the motor stator in
• Cut a hole in the supra-base (is there a better word?) for the PVC tube to sit on
• Cut some pieces of dowel to support the supra-base
That's it for drilling and cutting, now on to the NAILGUN!!!
Step 3: NAILGUN!!!!
Use the NAILGUN! to nail everything together (you can use a hammer and brads if you want...). Nail the motor to the board, the other pieces of dowel in place, and put the 2x4 in place so that it allows the dowel to spin freely, but in a controlled manner. If you have some molding handy, it can be helpful to keep the 2x4 in place. You can also nail the supra-base in place now.
Step 4: Attach the Pipe
Plug your hot glue gun in and glue the PVC tube to the supra-base. If you planned it right, you won't need to add pieces of wood to keep the tube on the board (I routed the hole for the belt wrong). While you're at it, glue the CPVC tube in place.
Step 5: Make the Belt
Take your airplane blanket and cut a strip that will wrap around the CPVC and the stator twice. Fold it in half and finagle the strip in place around the stator and the piece of CPVC . Sew the two ends together. For better durability, I recommend that you sew down the sides of the blanket to keep it from ripping.
Step 6: Prepare the Discharge Ball
If you haven't already JB Welded the two bowls together, do it now. Make sure that you push the bowls together so that they are touching, as JB Weld is not conductive. You could also weld the bowls together, but I lack a mask and rods for my DIY welder. Once the bowls are secure, attach the wire brush (it can be made of a piece of stranded wire splayed out) using a mixture of sand paper, solder, and whatever else you have to attach the brushes to the bowls and have zero resistance. An epoxy that conducts electricity would help here (does anyone know of one).
Step 7: Attach Everything
Place the discharge ball on top of the PVC tube and position the wire brush so that it is almost touching the blanket. Turn the motor on to make sure that the brush doesn't touch the blanket (because you don't have x-ray vision, listen for the sound of the fabric rubbing on the brush). If all is well, hot glue the discharge ball in place.