Build an Electrostatic Motor

This site gives information for building an electrostatic motor from 2 plastic soda (pop) bottles. To see a video of the motor in operation, click on the file "cap0001.mpg" below. Be patient - it's a big file (17 MB). For additional information on the procedure, click here.

Step 1: Base

Drill a hole in the wood just large enough for a bamboo skewer. The hole must be drilled as vertically as possible. Insert the skewer in the wooden base. The skewer serves as the axle for the rotor to spin on.

Step 2: Stator

Use the larger bottle as the stationary stator. Tape two pieces of foil (4 layers thick) on the bottle. These are the stator plates that will interact with the rotor plates. Cut tabs in the plastic and bend the tabs in slightly. Trim back the plastic to slightly less than the length of the foil. The foil tabs will allow charge to jump from the stator plate to the rotor plate, causing the rotor to spin. If possible, use some tape to insulate the foil tab so that only the tip is exposed.

Step 3: Rotor Bottle

Use the smaller bottle as the rotor. The rotor plates are made by taping 3 pieces of foil symmetrically on the bottle, keeping a separation of about 1 cm between the plates. The tape serves to insulate one plate from the next. Drill a small hole in the centre of the bottom of the rotor bottle for insertion on the bamboo skewer. Insert a screw inside the rotor cap in the exact centre to act as a "frictionless" pivot for the bamboo skewer.

Step 4: Assembly

Place the stator bottle on the axle. Next place the rotor bottle on the axle, ensuring that the bamboo axle is in the centre of the screw you put in the cap. You may have to adjust the length of the axle so the rotor and stator plates are properly aligned. Adjust the tabs on the stator bottle so that the foil tip comes very close to the rotor plate without rubbing. You may need to trim back the plastic tab a little but leave some foil extending past the end of the plastic. This way, if the foil tab touches the rotor, it won't slow it down.

Step 5: Operation

Using flexible copper wire, attach one of the stator plates to a Van de Graaff generator (or TV screen covered with foil), and the other plate to ground (e.g. a sink faucet). Turn on the generator or TV. It may take 10 or 15 seconds for enough charge to build up. You may have to give the rotor a gentle spin to get it going, but if it is made properly, it will start turning by itself. It should rotate up to 400 - 500 r.p.m.

Comments

[john500]

hi
i have a question, one part of copper wire goes connected to earth and to a static electricity fuel or to a baloon, the other part of wire... goes where?
thanks

[seccheus]

Will this design work in an linear format? If so can you build and example? I am working on a way to recharge an electrical vehicle. We should get together and do some experiments. Dante' 910-977-3607

[John Chase]

Not sure what you mean by "linear format". The original design used 3 bottles side-by-side - linear I guess. See link to William Beatty on my website. http://members.shaw.ca/jachase/

[seccheus]

Also will the motor work if I use a battery or does it have to be a VDG- high voltage- direct current?

[John Chase]

Has to be a source that generates static charge through electrons or ions.

[seccheus]

Will the motor work as a generator if I turn the center peace?

[John Chase]

no

[naitik007]

about how much power or electricity can it produce???

[John Chase]

It doesn't produce electricity. It spins as a result of static electricity. As far as power is concerned, it's not a strong "motor". Pretty low torque I would imagine. Mostly for fun to demonstrate another way to make an electric motor.

[toddjwood]

John,
I loved this instructable! it was the basis for my motor (see pic below).
I even added neon lights between adjacent plates and it works and lights up while turning! Thanks for the article!!
Todd

[John Chase]

Woah baby - that thing is really spinning!!! What did you use for the static charge? Or do you have some other electrical source? And you said "neon" lights? as in gas-discharge neon? Are they also powered by the static discharge? I bow down to the master!

[toddjwood]

I have used my Van De Graaff and I also have a 7.5KV negative Ion generator that I use as a HV power source. The neon light were from panel indicators and are slightly smaller than a tic tac. Here is a couple of pics for reference.

Thanks for the inspiration!!
Todd

[ghij]

cute??

[jayski20]

im just a little bit confused about our project.... how to make an electrostatic generator out of a ceiling fan motor?.... and can i have the materials used in making such thing...pls... and is an aluminum foil a good conductor of electric charge?....

[John Chase]

My project was an electrostatic motor. I don't know how to make an electrostatic generator, but there are lots of sites on the internet. Aluminum foil is a good enough conductor for hobby purposes. Not as good as copper or other metals.

[ftmatif]

i have this sience thing comping up... its kinda like the intel sience olmpiad only on a national level, so i need a project that is not only easy to make, but impressive.it can either be physics, biology or chemistry..... i need help and quick.....

[John Chase]

You want easy and quick and impressive. Tall order - not sure I can help. Building an electrostatically powered machine would be impressive, but not easy. But just the motor part might do.

[divyanshu007]

 how does the electrostatic charge cuse the rotor bottle to spin

[John Chase]

The foil on the inside bottle gets the same charge as the foil on the outside bottle, so they repel each other and the inside bottle spins to "get away".  Then the charge gets dumped off the inside foil, so now it attracts the outside foil, and it spins back again.  The cycle repeats over and over - pick up charge, repel, spin away, dump charge, attract, spin back, etc.

[ftmatif]

yeah i kinda figured out that bit myself :) thanks anyway