For my 8000th tweet, here’s how to make a truncated icosahedron from toilet roll tubes.👇

You’ll need 9 toilet roll tubes, scissors, pencil/pen, ruler, glue stick, time and patience.

Start by flattening and cutting each toilet roll tube into equal width strips. I found 9mm worked fine, but 8mm might be better.

Once they are all cut, you need to put them together. Here’s how to start.

Once you have 3 together, it’s time to build a pentagon.

Now you have a pentagon, you need to make each shape around the pentagon into a hexagon in the same way as before. Just add one extra edge.

Keep going until they are all hexagons.

Every hexagon in a truncated icosahedron has three pentagons and three hexagons adjacent to it. They alternate as you move round the hexagon.

Keep building in this way, making sure every pentagon is surrounded by hexagons only and each hexagon has pentagon, hexagon, pentagon, hexagon, pentagon, hexagon around it. The shape begins to take form pretty quickly.

To finish, you will have 3 pieces that you can’t seem to attach. You need to cut one of them. ✂️

Then arrange like this.

Then use some glue on the join and the other bits that need to be stuck together at this last vertex.

Finally, stretch out all of the pentagons and hexagons so that the vertices “lock” into place. See what other shapes you can make in the same way.

Huge thanks to @Ian_Willey for sharing the pictures that got me started on this.


You can follow @mrallanmaths.



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