Oxi module — folding instructions

These are folding instructions for the Oxi module designed by Michał Kosmulski. This module is my first published modular origami unit and was inspired by Thomas Hull's PHiZZ unit. Since I'm too lazy to draw nice diagrams, I just made photographs of the module at different stages of folding. The module is quite simple so I hope such pictures are clear enough.
The module was designed in 2005 and published in 2006 by Michał Kosmulski. Of course you are free (and encouraged) to use it for folding your models and to use it as an inspiration when inventing your own modules.
The pictures (diagrams) below are available under a Creative Commons license.

Creative Commons License Image thumbnails on this page and the full-size images they link to are licensed under a Creative Commons License (Attribution-ShareAlike; Ask me about other licensing terms).

Finished module and sample usage

Oxi module folding instructions Oxi module - finished truncated octahedron

Folding the Oxi module

Oxi module folding instructions

1. Start with a square piece of paper. Valley fold the sheet in half, then make two mountain folds to divide it into fourths ("accordion pleat").

Oxi module folding instructions

2. Fold along the creases created in step 1.

Oxi module folding instructions

3. Valley fold the left corner (45 degrees).

Oxi module folding instructions

4. Valley fold

Oxi module folding instructions

5. Mountain fold.

Oxi module folding instructions

6. Valley fold the loose end (45 degrees).

Oxi module folding instructions

7. Unfold along the crease created in step 5.

Oxi module folding instructions

8. Valley fold.

Oxi module folding instructions

9. Fold again along the crease created in step 5.

Oxi module folding instructions

10. Mountain fold the larger isosceles triangle in half.

Oxi module folding instructions

11. Finished module (rotated).

Assembling the modules

Oxi modules can be used to fold any polyhedron such that exactly three edges meet at each vertex. Two units are connected together in order to form a single egde of the polyhedron, then a number of these two-unit assemblies are connected to each other, forming the complete model. Each edge looks like a gable roof and each vertex is similar to a triangular pyramid.

Oxi module folding instructions

12. Prepare two modules and put them next to each other as shown in the picture. Usually, each edge is made of two modules of same color but here modules of different color are used in order to make the pictures clearer.

Oxi module folding instructions

13. Put the triangular flap of one module inside the other module's "pocket".

Oxi module folding instructions

14. Repeat step 13 on the other side. A single edge of the model is now complete.

Oxi module folding instructions

15. In each vertex, three edges meet. From this picture on, each edge consisting of two modules is a single color.

Oxi module folding instructions

16. First, join two modules by putting one module's "flap" into the other one's "pocket"

Oxi module folding instructions

17. Attach the third module to the second one.

Oxi module folding instructions

18. In order to complete the vertex (i.e. close it by attaching the first module back to the third), you will have to partially unfold the modules forming the third edge (orange in the picture).

Oxi module folding instructions

19. Join the two modules of the orange edge back together. One vertex of the polyhedron is now complete.

Oxi module folding instructions

20. The complete vertex seen from above.

Oxi module - finished cube Oxi module - finished truncated octahedron

21. Continue adding edges until the polyhedron of your choice is ready. Images show a cube and a truncated octahedron made from Oxi modules (click to enlarge).