This year, we wanted to showcase the idealised library with spiral staircase and cosy reading booths, which was the Christmas decoration at London St Pancras station last year (see St Pancras 2023 Christmas Tree ). The photograph used as the basis for the front cover and the inside images was taken by our son-in-law Gareth in November 2023.

How to make a hexaflexahedron using the enclosed template

First, let me mention that if you are looking for information about these on line, you will often find them called 3D hexaflexagons, flextangles, or kaleidocycles.

For those of you who don't trust yourselves not to spoil the template before achieving the end result, here is a PDF of the template that I hope you will be able to print: PDF of Three Templates. Hopefully you'll be able to print that from your browser -- you may need to select "fit to page" to scale the image to suit the size of paper. Please make as many copies as you like. If you want to draw one for yourself, just use equilateral triangles in the same pattern (you may want to stretch the linking joints a bit as I have done to help with flexing).

OK, once you have a template to use, here's how to proceed.

First cut out the unwanted parts:

Then reinforce the lines that go straight across the short width -- these will form the connecting hinges for the six tretrahedra that make up the hexaflexahedron and tend to fray with use.

Next, crease well along all the lines -- both diagonal ways as well as horizontal. Good creases will help form a neat shape and will help the flexahedron to turn smoothly.

Now you are ready to start gluing or taping. If gluing, use a good glue and wait for it to dry before flexing. First glue into a sausage ...

Once fully dry, you can try flexing your hexaflexahedron and embelish it as desired!

For those of you who like a challenge, you can extend the template by adding more triangles and make other flexahedra -- octoflexahedra, icosaflexahedra and such like. The longer ones will flex with a hole in the middle.

Enjoy!