4. Beautiful 3D model of triangles // The icosahedron // paper model скачать в хорошем качестве

4. Beautiful 3D model of triangles // The icosahedron // paper model

📌 SUPPORT MY WORK:   / chartamagica   The icosahedron is one of the five Platonic solids, next in simplicity to the tetrahedron and octahedron. It shares with these the fact that all its faces are equilateral triangles. In making a model of this polyhedron there are two effective ways of arranging five colours. They can be arranged so that each of the five appears around each vertex but then opposite faces will not be of the same colour. The second arrangement has opposite faces the same but one colour repeats itself around each vertex except the two polar vertices. Both of these arrangements are very useful, because many of the uniform polyhedra to be described later in this book have icosa-hedral symmetry. So you will find it profitable to have two models of the icosahedron illustrating both colour arrangements for future reference. You may begin both with the same initial arrangement of five equilateral triangles as shown. These form a low pentagonal pyramid without a base. The next set of five triangles may then be cemented to the pentagonal edge as set out in the colour table. Between these the third set of five easily find their position because only one more triangle is needed to complete the ring of five at each vertex. One more set of five then completes the model. #papercraft #papermodel #howto