Home > Polyhedral Toy > Delta-Star

Delta-Star is a polyhedral object which I invented in 1996.
The type of Delta-Star corresponds to Deltahedrons. It expands and shrinks. Especially highly symmetric tetrahedron,octahedron,icosahedron types and deltahedorn 6,10 can transform smoothly.

Furthermore tetrahedron,octahedron type and deltahedron 6,10 can be folded compactly by moving joint position.

Tetrahedron type(Tetra-Star)

Octahedron type(Octa-Star)

Icosahedron type(Icosa-Star)

Deltahedron 6,10 type photos.

How to make Tetrahedron type(Tetra-Star)

  • bamboo rods:diameter1.8mm * 18cm * 12rods
  • silicon rubber tube:
    inside diameter1.5mm * 2cm * 12pieces (for joint A)
    inside diameter3mm * 2mm * 6pieces (for joint B)
Construct as discribed below
  • Two bamboo rods corespond each tetrahedron edges.Put two rods through joint B.(left figure)
  • Construct bamboo rods at each vertex and join rods by joint A.(center figure)
  • Position of joint B may be nearly midpoint.
  • Don't insert rods through center 5mm of joint A.(for the sake of avoiding damage to rubber tube)
Tetra StarTetra Star

How to fold
You can fold like right figure when joint B is at center.
(standard position)
Tetra Star
If you move three joint B,
It can be folded linearly(upper figure),
or fold to planar form(lower figure).
Tetra Star


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