Introduction: World's Simplest Electric Train

Picture of World's Simplest Electric Train

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

Picture of 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"

Picture of 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!

Picture of 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

Picture of 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.


sste7395 (author)2017-12-02

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?

whoismorpheus (author)2017-10-22

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.

Snow_Tiger (author)2016-11-08

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

jgerry22 (author)Snow_Tiger2017-02-28

ive done this before and it cant go that steep

KJMagnetics (author)Snow_Tiger2016-11-08

No, it doesn't have enough power

MatthewR161 (author)KJMagnetics2016-11-10

What if we use two batteries in series?

KISELIN (author)MatthewR1612016-11-22

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

KISELIN (author)KJMagnetics2016-11-22

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).

Snow_Tiger (author)KJMagnetics2016-11-08


144920 (author)2016-11-29

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.

dave.vaness.79 (author)2016-11-20

Do you use dead soft or half hard copper wire?

dick55 (author)2016-11-14

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 !

fgeer (author)2016-11-02

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

KJMagnetics (author)fgeer2016-11-02

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

dick55 (author)KJMagnetics2016-11-14

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.

KISELIN (author)KJMagnetics2016-11-03

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

skrubol (author)KISELIN2016-11-03

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

Snow_Tiger (author)2016-11-09

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

Snow_Tiger (author)2016-11-09

please help me, my track and train does not even work

Snow_Tiger (author)2016-11-08

Also can there be more than one "train" in the 'tracks"?

KJMagnetics (author)Snow_Tiger2016-11-08


mdeudon (author)2016-11-06

Cool but yes the battery is in a shortcut. How long can it works this way ?

KJMagnetics (author)mdeudon2016-11-07

Not very long, a few minutes!

WilliamW6 (author)2016-11-06

really like this. gunna build one, gunna go nuts about it. the kids I teach deserve it. Good job guys. Experiments are the railroad to the future. ? ?

BeardedPapa (author)2016-11-03

Really neat. Being a retired (and tired) physicist, when I analyze the magnetic fields, it looks like it would run better if the magnets were put on the battery as so: S N -Battery+ S N . Have you tried that?

BeardedPapa (author)BeardedPapa2016-11-03

However, it might only run one way through the "track" in that case.

KJMagnetics (author)BeardedPapa2016-11-03

Unfortunately, it won't work like that. It just vibrates in the track and doesn't move!

MarianneM5 (author)KJMagnetics2016-11-05

They said that if you don't put the magnets right way (which is so that they's repel each other if it hadn't the battery between them) it would just vibrate, so I'm guessing that happened

BeardedPapa (author)KJMagnetics2016-11-03

Then, I'm just going to have to build one and do further testing to understand why. :)

Keith0923 (author)BeardedPapa2016-11-04

See the video posted by GuissepeV8 above and you will see why it doesn't work

BeardedPapa (author)Keith09232016-11-04

Thanks, Keith. You are right - that explains it.

Keith0923 (author)BeardedPapa2016-11-05

You're very welcome ?

KISELIN (author)KJMagnetics2016-11-03

Give it a little "cickstart" to owercome the "status quo" in the powerfield

fred_ (author)BeardedPapa2016-11-03

Flip both magnets and it will run in the other direction.

fred_ (author)BeardedPapa2016-11-03

Check Jan16 American Journal of Physics.

It's a pushmepull you. Pulling on the north pole at one end and pushing on the north pole at the other end of the battery.

The copper tube won't work. But drop a magnet down a copper pipe and see how slow it falls :) Strong magnet and less clearance in the pipe the better the effect.

The magnets complete an electrical circuit with the battery and portion of the coil it contacts. This movement energizes a new portion of the coil and round it goes.

No electrical contact no current in the coil so no electromagnet and no movement. The plastic tube or close to electrical contact won't work.

bennnyboi (author)2016-11-03

once i get enough wire and the magnets im gonna make a train track for it around my whole room

Louis_P (author)bennnyboi2016-11-05

The batteries wouldn't be able to complete long distances as it uses up all the battery life in a few minutes.

jeanluc.geronimi.1 (author)2016-11-05


Very nice instructable.

If i understand the battery is on a kind of shortcut.

Would it work with a rechargeable battery (Lipo 3,6v for exemple or would it burn the lipo ?)

Thank you.

Intensescroot (author)2016-11-04

Better contact Elon Musk...I think you just built his 'Hyperloop' train FOR him!

jpcota (author)2016-11-04

Many thanks for the link Giuseppe and dick55, never thought it was due to electrons! :-)

jpcota (author)2016-11-04

What exactly is the principle behind the motion?

dick55 (author)jpcota2016-11-04

Actually this is a self-powered solenoid.

GiuseppeV8 (author)jpcota2016-11-04

This is a simple video that explains the physics behind:

KJMagnetics (author)GiuseppeV82016-11-04

This is a great video! We reference that in our blog article about this.

Denis EduardoD1 (author)2016-11-03

Nice job!

Maybe if was used spherical magnets would be better, like this:

No, spherical magnets become physically unstable and can short, see the video posted above.

kimvellore (author)2016-11-03

I wonder if this will work in a copper tube and if it will be strong enough to move vertically. That will be a fun experiment. It will probably need some copper fingers on the magnet or aluminum foil as fingers on the magnet for better contact.

Keith0923 (author)kimvellore2016-11-04

It won't work in a tube, this is explained above also there isn't enough power to make it rise vertically. See the video posted above in the comments for full explanation of the physics behind why/how this works, it's simple but fascinating as are all physics experiments.

GrahamH27 (author)2016-11-03

hi what a fantastic idea. Why don't you think about using it in a commercial way, either as a toy or full size.

What are way to travel and green too. Ps please remember me when you become a

Nighter3D (author)GrahamH272016-11-04

My bet is due to energy comsumption. Between the battery terminals are 2 magnets with a negligable resistant and a Air core inductor. This project will drain the battery as fast as physically possible.

Let me do a quick estimation. Let's say that everything together (battery,magnet and coil) has a resistance of say 0.5ohm (reality is probably a lot lower). at 0.5 ohm the current would be 3Amps and consumption would be 4.5watt. The battery will get drained very fast.

About This Instructable




Bio: 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 ... More »
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