Net for the DODECAHEDRON (The Platonic Solids of Ether)
12 Pentagonal faces, 20 Vertices, 30 edges, Icosahedral (2,3,5 fold) symmetry.
Dodecahedron (डोडेकहेड्रॉन) - द्वादशफ़लक - A three-dimensional shape having twelve plane faces, in particular a regular solid figure with twelve equal pentagonal faces.
Construction drawing for the first half of the net.
Method:
1. Draw a circle centre O radius OA, and the pentagon CHJKG within as follows: draw any honzontal diameter AB through O, and then the perpendicular vertical axis CD (equal ares above and below from A and B) Find the mid point E of OA (arc radius OA from A to cut circle above and below, and connect), Draw an arc centre E radius FC my cat BA at 1: draw arc centre radius CF to cut circle at G. CG is une side of our pentagon, which can be 'valled ' around the circle with the compasses to find the other points H, J and K. Adjust il necessary so that the five points are equally spaced around the circle.
Construction drawing for the med half of the net. Note that this mast be of the same my as the first half.
With some care the whole net can be drawn out as one drawing. This requires same skill in the projection of lines from the first half (on the left within the circle) to ensure accuracy - which is why many will find it easier to make the net in two halves.
The two halves of the net drawn out on card and cut out (top), and glued into dishes (bottom).
2. Draw a pentagram (star) within the pentagon by drawing lines from each point to all the other points (from G to H and J; from C to J and K, etc). In the middle of this pentagram is a smaller pentagon LMNPQ.
3. Draw the diagonals of this inner pentagon and extend them to intersect the main pentagon, creating five similar (same size) pentagons surrounding the inner one.
The two halves joined to complete the DODECAHEDRON.
4. Mark the cut and fold lines as shown.
5. Add tabs as shown.
6. Make a second net of exactly the same size; but omit the outer tabs.
7. Cut out along the solid lines: score along the dashed lines. Fold upwards along the scored lines.
8. Glue both nets carefully and progressively (tabs inside) - one or two tabs at a time. Make sure the outer tabs are not folded too much as they need spring to engage with the second half Then glue the outer tabs and join one half to the other.
9. Clean up and decorate as you wish. 👍
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