An explanation sheet for making
Straw Polyhedrons


Materials and tools
  • 6mm diameter straws (in order to make parallel connectors)
  • 4mm diameter straws (in order to make edges of polyhedrons)
  • A ruler
  • A pair of scissors
  • Proper maths text book


Example 1: Making a regular tetrahedron
(1) Preparation of connectors
1. In order to make parallel connectors cut 6mm diameter straw into 2 cm length. Make twelve 2 cm pieces.

2. Make a slit in the middle of the connector. Do not cut one third of the circumference of the straw.
3. Hold the both end of the connector and fold it to open the slit.
(2) Preparation of edges
4. 4mm diameter straws are used to make edges. We use opposite side of the mouthpiece as an edge. Cut the edge into proper size. We use twelve 4mm diameter straws for making a regular tetrahedron. 5. Make one straight slit on each mouthpiece side of 4mm straw.
6. Connecting edges, insert a mouthpiece into an edge end of another 4mm diameter straw.

(3) Assembly of connectors and edges
7. Bend twelve 4mm straws 8. Insert a 4mm straw into two connectors like the picture above. 9. Make another combination of 4mm straw and two connectors. Connect the two combinations.
10. Two edges are connected. 11. Connect one more edge. 12. Insert remained slit mouthpiece into free end of the edge in order to make a equilateral triangle.
13. Insert 4mm straws into connectors like above picture. 14. Put connectors and 4mm straws like above picture. 15. Insert a 4mm straw into a free open end of an edge.
16. Insert new 4mm straw edge into connectors. 17. Connect 4mm straws. Repeat 15-17 two times. 18. Finished regular tetrahedron.

Example 2: A regular hexahedron
Materials: Twenty four (24) 4mm diameter straws and 24 connectors
Finished regular hexahedron The expansion of the regular hexahedron

Example 3: An irregular hexahedron
Materials: Eighteen (18) 4mm diameter straws and 18 connectors
Finished hexahedron The expansion of the irregular hexahedron

Example 4: A regular octahedron
Materials: Twenty four (24) 4mm diameter straws and 24 connectors
Finished regular octahedron The expansion of the regular octahedron.
An octahedron consists of eight equilateral triangles.

Example 5: A regular 12-hedron
Materials: Sixty (60) 4mm diameter straws and 60 connectors
Finished regular 12-hedron The expansion of the 12-hedron
12-hedron consists of 12 regular pentagons.

Example 6: A regular 20-hedron
Materials: Sixty (60) 4mm diameter straws and 60 connectors
Finished regular 20-hedron The expansion of the 20-hedron
A regular 20-hedron consists of 20 equilateral triangles.

Example 7: A skeleton of soccer ball
Materials: One hundred and twenty (120) 4mm diameter straws and 120 connectors.
Soccer ball skeleton Making the soccerball
This soccer ball skeleton consists of 20 equilateral triangles and 12 regular pentagons.


"Straw Polyhedrons" Copy right JICA Senior Volunteer Hideo Nakano (Sept 2005)
inserted by FC2 system