In this article, we are going to show you how you can create the simplest (possibly), but by far the most awesome (definitely) DIY electric train by using nothing more than a battery, some bare copper wire and two magnets. Before you stand aghast in disbelief and tell us it can’t be done, make sure you check our article on how to make a basic electric motor with almost identical materials.
When you combine magnets, a conductor and movement you get electricity and when you combine electricity and a conductor you get a magnetic field. When you combine this magnetic field, with another magnetic field (provided by the magnets) you get…movement! This is how it works…
How does the simple electromagnetic train work?
When the battery is placed inside the coil and both magnets are touching the coil it produces a closed circuit between the two magnets, and current flows. As the current flows through the conductive copper wire a magnetic field is created around the wire. This magnetic field interacts with the magnetic field created by the neodymium magnets in a way that repels the magnets on one end, and attracts the magnet on the other pushing the battery through the coil.
As the train moves, the process repeats in the section of the track between the two magnets, making it run until the battery has no juice left!
To make this train, you need coiled bare copper wire, and lots of it – this acts as the conductor. It is important that the wire is bare (not enamelled) and is coiled as tightly as possible only just wider than the diameter of the magnets being used, which in turn should be the same diameter or slightly larger than the battery being used. Next, you need to take your battery (tip: fully charged rechargeable AA batteries work best because they will provide greater power and expire pretty quickly) and add a magnet on each end. Follow our step-by-step instructions below.
Quick step instructions
1) Get a battery, rechargeable AA type works best.
2) Locate a rod or tube that is just a little larger in diameter than the diameter of the battery. We found that a piece of 15mm diameter copper pipe is perfect if using an AA battery.
3) Take your bare copper wire, we found 0.8mm diameter works well, and wind it tightly around the rod, tube or pipe to create a tightly bound coil. Taking care to slide each coil together as you wind.
4) Choose the right magnets – If you are using an AA battery, 15mm diameter x 5mm thick neodymium disc magnets are perfect. If you are using a larger battery, make sure you choose magnets that are larger than the battery’s diameter. Click the image below to buy these from first4magnets.
5) Place one magnet on either end of the battery. You need to make sure both north poles (or both south poles) are facing each other when the magnets are attached to the battery. Tip: Carefully hold one magnet in each hand in a way that prevents them jumping together and feel which sides repel each other, then place on the battery.
6) Slide the battery inside your coil and watch it go! Tip: If the battery is being forced out of the end of the coil, simply spin it around 180 degrees.
Caution: Be careful, if the battery is allowed to run continously for more than a few seconds it will begin to get hot. Handle with care and never leave children unsupervised with magnets.