These Hearts Are on Fire

Introduction: These Hearts Are on Fire

I am re-inventing myself as an inventor, after too many years as a mechanic! I enjoy learning fr...

The homopolar motor is the simplest motor in the world. It's made of a battery, magnet, and a piece of wire.

In this case, I use a AA size NiMH battery, a 1/2 inch x 1 inch neodymium supermagnet, and some bare 10 ga. copper wire. I bent the wire around a D-cell battery to form the heart shape.

This video shows several variations of this motor, using two different wire-form heart shapes as the basis. In the end the two hearts unite to become one.

Background music "This Heart's On Fire", courtesy of alternative band Wolf Parade.
This video dedicated to all Hearts on fire everywhere!

You can order neodymium super-magnets from K&J Magnetics



    • Tiny Home Contest

      Tiny Home Contest
    • Creative Misuse Contest

      Creative Misuse Contest
    • Water Contest

      Water Contest

    67 Discussions

    This was so simple to make .Thank you the ladys love them.

    Will this kind of gage wire work?: It says AWG 10 but I realized that it's different when I got home already.

    Will this kind of gage wire work?: It says AWG 10 but I realized that it's different when I got home already.

    I am a techno-phobe, but your project seems possible for a person without any experience (me) I love your instructables. I don't have the skill or understanding how to make make them, but I think you have neat ideas!

    1 reply

    Thanks for the complimentary comment! The Hearts homopolar motors are a great entry point for non-technical folks to play with the forces of magnetism and electricity. The Hearts are relatively easy to make, especially in a wire gage that is thinner than the heavy 10 gage that I used. The Tesla CD Turbines I make are built are simple...but not necessarily easy. There are plenty of little details that make the difference, and sometimes even I still make a turbine that simply doesn't work. However, each effort to make something stretches one's abilities, tolerance levels, knowledge and most important, one's fun experiences in this world!

    ive tried to make some of these motors but none of them work i need to now wat gauge of wire u used and maby i need a bigger magnet idk can u help?

    1 reply

    Sure, I can help! Are you using a neodymium magnet, preferably at least 1/2 inch x 1/2 inch size? I used 10 gage household wiring copper wire, but any size up to 20 gage will work. Thin wire can heat up your fingers! The wire must be bare where it contacts the battery and the magnet. (some craft wire have a coating that has to be removed with sandpaper) The Heart with two legs that touch the magnet has to be adjusted so the legs have a gap to the magnet. If they are both touching at once, there will be too much friction and the motor will not work. The battery must be powerful. I prefer the rechargeable Duracell 2650 MaH. A regular Duracell will work too, but it won't last very long. Some batteries are not very magnetic and won't work. Try these things, and let me know how it goes.

    About how long do the spin for? Have you ever thought of using one of these as a joule-thief for rechargeable/standard batteries?

    2 replies

    The heart-shape homopolar motor will usually go for about 3-5 minutes, sometimes up to ten or fifteen minutes. That's with a heavy-duty 2650 MAh NiMH Duracell rechargeable. Doesn't a Joule-Thief collect the residual power in old batteries? How might this motor work that way?

    I always thought that they simply deplete the old batteries completely before you dispose of the said batteries, I could be wrong. Although you have given me a good idea if it hasn't been done yet. You could make a rig to take nearly-dead batteries and use their "dying-breaths" to charge a single/multiple rechargeable battery(s).


    dammit....i cant seem to make this and i just shorted a battery and now im scared to keep on trying to build one.

    8 replies

    OK, don't panic...let's made a heart shape? with open or closed bottom? what size magnet? It is neodymium, right? what size battery? How did it short? If you can answer some of these questions, I can help. These motors are simple, not easy. They seem to have good days and bad days, hehe.

    i did not make a heart shape, i tried to make the 5 speed without the coins, seeing as im not in canida. the size magnets are about 3mm tall, 12mm wide (not sre, thats a guess. the magnets used are "black hole" earth magnets (which im pretty sure is neodimium, theyre silver, not black like a refrigirator magnet.) the size battery was aa and i also tried aaa. the way it shorted was an attempt at someone elses instructables on this and the wire touched the top while the wire on the bottom touched the magnets the magnets touched the batter and wahlah, a super heated wire IN MY HANDS i got freaked out becuse one time i tried to biuld a rc thing out of an old rc boat and i heard a woosh and saw a orange glow under my project and a puff of smoke, and proceded to say "mummy im scared" (that was like a couple years ago)

    Ok I get it now...I thought you were building the heart from the coathanger wire, which won't work. If you use the coathanger wire as a support, it should work similar to the five-speed video. You must be sure of a bare connection to the coathanger; there is usually varnish or paint to scrape and sand off. And you must use a copper wire to the magnet. For the motor you tried in your hand, use a bigger copper wire so it won't heat up so much. Keep at it...yes it can get a little dangerous, but (as in life!), if you pay close attention, chances are you won't be hurt.

    thanks but how do i make the simple five speed without that shifter and the coins? i dont have canadian coins or copper wire.

    Here's another of my homopolar movies, called "Homopolar Motor Variation"

    I use a piece of welding rod for the stand. Welding rod is like coathanger wire, but it has a copper coating.

    You will need a short piece of copper wire to attach to the hanger support. You can use coathanger, but the paint or varnish must be sanded off where the copper wire makes contact , and the coathanger filed down to a smooth surface where the battery hangs on.

    You can try washers instead of coins.
    Good luck!

    HOLY F************K!!!!!!!!!!!!! IS THAT NEODYMIUM???!!!! THAT MAGNET IS REALLY STRONG!!!!!!!!!!!!!!!!!!!!!!!

    okay, but how does the wire bottom wire go near the magnet without attracting to it and stopping the motor?

    The bottom wire is copper, and should not attract the magnet. It is wrapped around the sanded-off coathanger for good contact. It needs to lightly touch the magnet to complete the connection and make it turn.