Stop the Train! Magnetic Brakes for a Maglev Train

Building Your Train

This video and the following written instructions will show you how to assemble your train. Attention to detail and patience are needed for this project. After building, you will need to make adjustments to get it working perfectly. The train floats above the tracks well once everything is lined up carefully. See the FAQ if you have trouble getting your train to work.

Maglev Train Assembly Instructions

Assembly instructions for your maglev train.

https://www.youtube.com/watch?v=KQH2UhHss6c

1. Before you start building your train, check to make sure you have the right magnetic tape. If you have monopolar magnetic tape, the strips of tape should repel each other. You can go ahead and use the monopolar tape as is. If the strips of your magnetic tape attract each other, the tape might be bipolar or multipolar. In that case, you will have to repolarize your tape first. Follow the instructions in step 7 of the FAQ section for this project to repolarize your magnetic tape. Once you are done, your magnetic strips should repel each other.
2. Peel the paper backing off the two short magnetic strips and attach them to one side of the wooden block, as shown in Figure 2. The edges of the strips should line up with the edge of the block. This block will be your train car. Note: if the magnetic strips are not sticky enough to stick to the wood on their own, use clear double-sided tape.

Figure 2. Magnetic strips attached to the wooden block.

2. Cut a piece of wood or cardboard at least 24" long by 3" wide. This will serve as the base for your train track.
3. Using one of the long plastic angle pieces as a straightedge, draw five lines lengthwise on your base as shown in Figure 3.
   1. Draw a center line down the middle of the base.
   2. Draw one line 5 mm to each side of the centerline.
   3. Draw one line 20 mm to each side of the centerline.

Figure 3. Dimensions for lines you will draw on your base.

4. Attach the long magnetic strips and plastic angle pieces to your base, as shown in Figures 4 and 5. Pay close attention to the spacing, it is important for getting your train to work properly.
   1. Peel the paper backing off the long magnetic strips. Carefully place them on the base so their inside edges line up with the lines 5 mm from your centerline, so the strips are 10 mm apart. Note: if the magnetic strips are not sticky enough to stick to the base on their own, use clear double-sided tape. Make sure you press down firmly so they stick in place.
   2. Use double-sided tape to attach the plastic angle pieces to the base so their inside edges line up with the lines 20 mm from your centerline, so they are 40 mm apart.

Two plastic angle pieces are placed parallel to each other on a cardboard sheet with a 40 millimeter gap between them. Two magnetic strips are also placed in parallel between the plastic pieces and should have a gap of 10 millimeters.

Figure 4. Cross-sectional view of the spacing for the magnet strips and plastic angle pieces.

Figure 5. Picture of a completed track.

5. Place your train on the track with the magnetic strips facing down. It should hover parallel to the tracks as shown in Figure 6, and you should be able to slide it back and forth without getting stuck. If your train does not hover as shown in Figure 6, see the FAQ for troubleshooting information.

Figure 6. Train hovering parallel to the tracks.

6. Build a magnetic "stopper" on one end of your track, as shown in Figure 7.
   1. Cut a small rectangular piece of cardboard, about 7 cm by 5 cm.
   2. Use tape to attach the piece of cardboard at a right angle to one end of your track.
   3. Use double-sided foam tape to attach a rectangular magnet to the cardboard. Make sure the magnet is at the same height as the wooden block of the train when it is floating above the track, and is centered between the two plastic pieces.

Figure 7. A magnetic stopper at one end of the track.

7. Use double-sided foam tape to attach one rectangular magnet to each end of your train, as shown in Figure 8. The magnets are heavy, so you need one on each side to keep the train balanced.
   1. Important: Test the magnets to see which side repels the magnet that is attached to the stopper. Make sure this side of the magnet is facing outward when you tape it to the train. Otherwise your braking system will not work, and your train will be attracted to the stopper instead of pushed away from it!

Figure 8. Magnets attached to both ends of the train.

8. Elevate one end of your train track using several books, as shown in Figure 9. The exact height of one end of the track does not matter for this experiment (see the Variations section for an idea about how to measure the effect of this height).

Figure 9. Maglev train track placed on an incline using some textbooks.

Collecting Your Data

1. Practice using your maglev train's stopper. Gently place the train about halfway up the track and let it slide down toward the stopper. The train should come to a stop before it touches the stopper. There are a couple problems you could run into, so do not worry if you need to adjust a few things before your stopper works nicely:
   1. If your train jumps off the tracks, it might be going too fast. Try starting it farther down the ramp, or decreasing the angle of the ramp.
   2. If your train gets stuck before it gets close to the stopper, there might be too much friction between the train and the plastic angle pieces. Try moving the plastic pieces apart slightly, or increasing the angle of the track so the train slides faster.
   3. The magnets on your stopper and the train might not be well-aligned. This can also cause the train to jump off the tracks, and the sides of the magnets to snap together instead of staying spaced apart. If necessary, adjust the height of the magnet on your stopper.
   4. Once you have your track adjusted so the stopper is working well, leave it in place. Use a pen or pencil to mark the approximate starting place on the track that works well.
2. Now that you have seen how the stopper works, what do you think will happen when you add more magnets to the stopper?
3. Create a data table, like Table 1, in your lab notebook.

4. Let the train slide down the track and come to a stop.
5. Measure the distance between the stopper magnet and the magnet on the front of the train, as shown in Figure 10, and record it in your lab notebook. This counts as one trial.

Figure 10. Measure the distance between the two magnets, shown with the red arrow.

6. Repeat steps 4–5 two more times, for a total of three trials.
7. Now, add a second magnet to your stopper, as shown in Figure 11. It should snap into place directly on top of the first magnet (if the magnets are pushing away from each other, flip the new magnet around).

Figure 11. Second magnet added to the stopper.

8. Repeat steps 4–6 with two stopping magnets stacked on top of each other. Make sure you record all of your results in your data table.
9. Add a third magnet to the stopper and repeat steps 4–6.
10. Add a fourth magnet to the stopper and repeat steps 4–6.
11. For each number of magnets, calculate an average for your three trials and enter it in your data table. For example, say that for one magnet you measured distances of 18, 22, and 20 mm. The average is (18+22+20)÷3=20. Ask an adult if you need help calculating an average.
12. Create a graph with the distance between magnets on the vertical axis and the number of magnets on the horizontal axis. See the Create a Graph website if you need help creating a graph.
13. How does the distance between magnets change as you add more magnets to the stopper? Is this what you expected based on your background reading about magnets?