Simple generator: AC electric generator for science fair

Today we’re building the world simplest electric generator. PLASTIC, that’s not simple! …so we will do the cardboard version. For this we’ll need wire: enamel coated
spools of wire from “Radio Shack.” Or …you can find solenoids from surplus junk-shops. Get spools of wire out of them. Magnets. Large ceramic block magnets. “Radio Shack” again, or I found these at “Home Depot.” A specialized light bulb. 1.5 volts, twenty five milliamps. It’s a “Radio Shack” part, and a nail, and Cardboard. Measure it out and mark it according to instructions on the web site. Website’s listed at the beginning and
ending of this video. Try to get it very square. I grabbed a
Post-it notepad to get square. and try to align it with the lines in
the cardboard Cut it out. I prefer a razor-knife, but kids
probably should use scissors. But the razor-knife gives nice flat edges. Nothing crushed or bent. Crease it along the lines, so it folds right there Fold it, so there’s a small side on the inside. You might have to mess around
with it because it has to have a “slip fit” on
the magnet. Make it a little wider there. Then to poke the nail-hole, let’s draw an “X” to the corners. Find the exact center. CENTER! Poke the nail through one side. Oops. There. And now get it exactly vertical; perpendicular that way, and that way. Then… enlarge the holes a bit. We want this thing to easily spin. Let’s test the four magnets. Get it somewhat centered. Make sure it it spins
very freely. To wind two or three hundred turns, I just stick my spool on a plastic pen. Pull off some excess and
stick it inside so we have plenty of lead wire. Tape it off, then off we go. Now try to make it in two lumps, so there’s plenty of space
for the nail. Of course don’t wind it across the hole. It has to go around
the cardboard. Don’t wind it too tight, because after a few hundred turns, the
pressure can build up and crush the cardboard. Wind lightly. And 300 turns will let you turn the magnet
fairly slowly and still light the bulb. 200 turns if you’re lazy. When done, tape it off. Cut to length. Cut off the excess so that we
have something to work with. Clean off all the red plastic from about 1 inch of the
end of the wires. Make sure the whole thing is a nice coppery color and not red. Tiny light bulb! “Radio Shack” 272-1139. You can’t use normal light bulbs
on this; this is a 1.5 volt, twenty five milli-amp bulb. Let’s get some extra wire; clean more plastic off. Oh, you can use …from mail-order, a #48 or #49 bulb. They are the same bulb, just different bases. This is a #48 with a screw base. You’ll have to crank your generator much
harder to get this one to light. The Radio-Shack bulb is better;
it’s more sensitive. Twiddle the wires solidly together. Lots of twists. Or solder it if you have a
soldering iron. Now in this one I’ve put little
spacers between the magnets. And got it well centered, so it spins
very nicely in there. I used little plastic spacers, little
pieces of cut Plexiglas. Now if you want to get fancy, sawing rings of black ABS sewer pipe and Plexiglas, you end up with something like this. A much classier version of the generator.

100 thoughts on “Simple generator: AC electric generator for science fair

  1. Whenever I try to spin the nail with the magnets on it they slip and fall off. Also if I place the 2 magnets at the opposite end of the nail they clump together into 1 group. The box fits perfectly in with the magnet width. Please help I need it ASAP for science exhibition.

  2. Hey thanks for showing me how to make this! One question: I can only find 1.5 V 40 mA mini bulbs at Radio Shack, I've called around but all the stores near me are sold out of 25 mA. I saw on your website you use a 40 mA also, should this work?

  3. What grade would this project be recommended for? I'm in the 8th grade, would this be suitable? i find it very interesting. Please answer asap as i will need to prepare a report very soon. Thanks! 🙂

  4. I'm having a lot of trouble finding the 1.5 volt lightbulb… Do you know any CANADIAN sites I can order from? Other stores are charging 30- 50$ for shipping!

  5. Hello I am working on this for a science fair and can not get the bulb to light. I have the same radio shack bulb. I don't think i have the wires correctly placed. Does it matter which wire goes on the long leg of the bulb? I have the last wire (meaning not the one i taped to the box) on it.

  6. i have a physics project to build an alternator like yours, but the twist is i need to generate a minimum of 25V what do you suggest i do?

  7. where exactly did you tuck the first end of the wire?

    is that the other pole you attached to the light? i didn't notice where you had it

  8. Hi, Thank you for showing us how to do this. Since you posted this video Radio Shack went out of business. Do you have recommendations as to where else i can purchase these items? Specifically the light bulb. I'm having a hard time finding the correct one.


    Bhai log isse dekhna mat bhoolna or ho sake to comment and subscribe bhi kar lena 🙏🙏 apna blog ha

  10. @wbeaty can i do this experiment with a larger cicumference copper wire instaed of a thin copper wire …..????

  11. I'm having a miserable time finding magnet wire. (locally) Is beading wire the same thing? Or is that something different?

  12. Fake video .It did not worked ..I tried this..
    Is any one who successfully made it..??( Sure not anyone )
    And it is not for any school or college project.Your teacher will throw it away…

  13. This is single phase, i know. But, what if I wanna Bust-A-F*** some LEDs, can this be easily converted to 3 phase generator?

  14. Would the magnetic feild reach the the outer wire loops if i used #35 wire and did 3000 loops with rare earth magnets?

  15. I followed the instructions on your website with slight changes (i added about 4 times more wire) and the 3v bulb i powered kept flickering on and off is there any way i can make it stay on?

  16. On the website you gave instructions to make a more powerful generator, and i would like to know if it is necessary to use smaller wire and why.


    Ps. Would it get 120 volts?

  17. You can find something like this on the Avasva page. Full step-by-step instructions right on your desk.

  18. Today My son and I made this generator. So simple! It's working! I love science! thank you

  19. 6:53 My class is laughing there heads off at this part. In fact, my class laughed at every part, they should act like a middle schooler. (the thing is that my whole class is a middle schooler.)

  20. 4:09 I need this for my model in science class and I couldn't see this part like, did you wrap it around the magnet? Did the wire come out of the other side? I'm confused..

  21. does a stronger magnet provide more power or is it all in the amount of turns or thickness of wire?

  22. First of all, let me tell you what material I have used.

    Cardboard – size as mentioned in the instructions

    nail – more than 8 cm long

    copper wire – 120m length – (picture attached for ready reference)

    magnets – 4 bars –

    My queries where I need help from you:

    1. Kindly confirm if the material that we are using are the correct ones. We can not buy anything from Radio shack as advised in the video because they do not deliver in Australia.

    2. In the video, the guy mentions to use some kind of spacer between the magnets. What that spacer is and how to use it.

    3. Instead of cardboard, can we use plastic or acrylic sheet, like it is shown in the starting of the video?

    We are really relying on this video to make the simple generator and win a prize in the school science competition.

    Your help in this regard is much needed and highly appreciated.

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