World's Simplest Electric Train





Introduction: World's Simplest Electric Train

About: We are a supplier of neodymium, rare earth magnets. We also love to conduct experiments with our magnets and build unique projects with them! We have several engineers on staff who are always thinking of new...

With just three everyday items, you can make the "World's Simplest Electric Train!" This is a fun, simple, yet great science experiment.

Materials needed:

20 gauge copper wire (non-insulated).

AA Battery

Two 5/8" x 3/8" neodymium magnets (our product DA6).

Step 1: Coil the Wire

The first thing you'll need to do is coil your copper wire! You can do this by hand, but it will take a long time and it gets tedious.

We used a 5/8" diameter dowel rod attached to a drill to quickly coil the copper wire. The video shows how. We used 20 gauge wire, in 50ft spools.

If you use the method we did, you'll want to drill a small hole through the diameter of the dowel, then feed the wire through this hole and bend it around the dowel. This will create a good starting point for the coil!

Step 2: Make the "train"

This step is pretty simple. Take your AA Battery and your magnets and put the magnets on either end of the battery.

IMPORTANT: You want to make sure that the magnets are repelling. So that means the south poles of each magnet need to be facing out, or the north. It doesn't matter which, but it does matter that if the battery wasn't there, the magnets would be repelling. (For help, watch the video at the end)

If your batteries are oriented incorrectly, you will know because the battery will just vibrate once placed into the copper wire.

Step 3: Make Your Track and Have Fun!

That's it! Truly simply.

You can make your track into all sorts of different shapes and can really have fun with it. Watch the video to see what we did!

Step 4: Experiment

We tried out different batteries, magnet sizes, and different gauge copper wire. We highlighted what we found worked best, but there are other options. Check out the table for some other options. This could be a fun, science experiment to see what works best.



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    Please be positive and constructive.




    i am a long time fan of K& J magnetics and a customer. The magnet stuck to the negative end of the battery is obviously going to stick quite well, but the positive end could possibly come out of position and increase friction due to the much smaller size of the positive terminal.

    Why not put a small steel washer big enough to fit over the positive end that is smaller than the battery's outer diameter and stick the magnet to that, to provide a more stable base and more mass for the magnet to stick to?

    I hasten to add that i have not built this as yet, so this is just appoint of of conjecture on my part.

    Will it work on n50 neodymium magnet on AAA battery?

    I am doing a science project with changing the distance between the coils, however I have a question. How do I measure the velocity of the train?

    Awesome technique. I loved it, my kid loved it. He is choosing this for his science project. He also came across another tutorial - . He is asking if he I can combine both and show in a project but he is confused wether one say electric and another one says magnetic. When i read both have similar concept but I am not very good at science. So asking if he can combine both.

    Can the train climb up on a supported angle? I mean really steep

    6 replies

    ive done this before and it cant go that steep

    No, it doesn't have enough power

    What if we use two batteries in series?

    If you put them batterys in series you'll get battery1 + battery2 +battey3 =

    1,5V +1,5V +1,5V gives you 4,5V Comprende?

    If you put put them parallel you got the accesibilty of that them Amps they can provide, still 1,5V in output

    Actually, the efficient "work" named "P" is as power in a factor in electricity, (and ower all), P=U*I, Hmm... to define "P" ..I think the "P" is about the same thing as lifting a weight of 1Kg from a niveau of 0 to 1meter in 1 second. Correct me if I'm wrong.

    As in electricity we allways talk about "Watt's and Amp's", Com'on "Watts" are the product, (Power), delievered by Volts*Amps, how hard can that be to understand, (not you).

    Can you replace the batteries. Instead of one magnet at each end can I use two 0.5 inch magnets on each end. I have thin magnets. Using them will save me from purchasing more. She who must be obeyed is also Scrooge.

    Do you use dead soft or half hard copper wire?

    DA6 magnets really stick together! I couldn't slip one off the other. So I made a simple tool to make it easier. I drilled a 5/8 inch hole, slightly less than 3/8 inch deep, centered in the long side of a piece of 2x4 wood. This supports one magnet while pushing firmly down on the other and makes it easy to separate it at the bottom of the slide.

    I also verified that it is easy for them to give you a bloody pinch if you are not very careful !

    Can you wind the copper around a plastic pipe. Then the battery won't stuck in the windings!

    4 replies

    The magnets need to come in direct contact with the copper wire!

    I've been thinking about using a table saw to cut a length-wise slit in "1/2 inch" PVC pipe, then using steel spring wire on the magnets to maintain contact with a coil wound around the outside of the pipe. The inner diameter of 1/2 inch (normal-pressure Schedule 40) PVC pipe averages 0.622 inch, which is almost exactly the stated diameter of the 5/8 (0.625) inch DA6 magnets. Actually, my magnets measure less than 5/8 inch diameter. I took my battery/magnet assembly and dropped it into 1/2 inch pipe and it passed easily through a 3 foot length. I haven't researched conductive spring wire (or other ferrous-type material) which should lightly drag on the coil and contact more than one coil at a time.

    Minimum wall thickness of the pipe is 0.109 inch, so the coil diameter is larger than one wound on a 5/8 inch dowel. However, the magnetic field strength at coil center is not a function of diameter; it only depends on current and number of turns. Also, the PVC wall material should not affect the field.

    Or, "allmost" in direct contact. All them materials to be magnetic, (Hmm... Iron, Neodym.. etc.), have a permebaeality in which level they can't take more magnetivety, so, the distance between the Source and the Drain could be such low as zero, (at least close to that),

    This instr. is one of them ewer, (my readings), best. Gonna do this

    Close enough to pass electrical current through the magnets to the copper.

    i have the right track i have alkaline AA batteries and small neodymium magnets