Make a levitating Lego Santa sleigh
Combining Lego and magnets opens up a whole world of fun and creativity; here, we will show you how to make a Christmas decoration with a difference. As well as being fun to make, it helps you learn about magnets too.
If you or your children have other Lego kits, you will no doubt be able to piece together the bricks needed to create a Santa sleigh bursting with festive funk. You don’t have to copy ours, there are lots of designs to be found online. Will you decide on the traditional reindeer powered sleigh or will you upgrade Santa to jet power – after all it is 2015!
Here are some we’ve found, or you can use Lego’s free Digital Designer tool to create your own, then order the bricks you need direct from Lego.
Once you have created Santa’s sleigh, you need to create the all-important track. The purpose of the track is to provide a surface which you can apply magnets to and prevent the sleigh moving from side-to-side as it floats, as any degree of sideways movement will prevent it from working. We created a track that fits inside the legs of the sleigh so you can see how it works and made sure the legs of the sleigh fit snug to the side of the track to stop any sideways movement.
To create the repulsion needed to float Santa’s sleigh, you need magnets; more specifically, 12.5mm wide self-adhesive magnetic tape. In our model, we applied the tape on the underside of the sleigh, running the full length. We then placed the same tape on the track so the two magnetic faces were pointing towards each other. It is important to use the same polarity tape on both the sleigh and the track, either both polarity A or both polarity B. If you use A and B polarities together the two pieces will attract rather than repel.
How does this work?
Every magnet has at least one north pole and one south pole, if you cast your mind back to school science lessons you will recall that opposite poles attract, while identical poles repel. Magnetic tape is actually magnetised with a striped polarity with a number of alternating stripes of north and south poles running the length of the tape in a north-south-north-south pattern. When two pieces of the same tape are arranged with their identical poles aligned directly on top of each other, the two pieces of tape will repel each other sufficiently to support the weight of the sleigh. This gives the appearance that the sleigh is floating and the reason you can move it up and down the length of the track without any friction!