This is full of ready to make dazzling polyhedra.

Cut and Assemble 3-D Geometrical Shapes...

Making the ...
DICE of the GODS We thank Mrs. Barbara Townsend for this design activity.
here is what you will need

To create the "Dice of the Gods", otherwise known as the five platonic solids: tetrahedron, octahedron, cube, icosahedron, and dodecahedron, you will need:

  1. several greeting cards or pieces of colored card stock or even cereal box sides
  2. a compass for drawing circles
  3. a ball point pen
  4. a ruler or straightedge
  5. a pair of scissors
  6. a stapler or glue if you prefer
draw a circle pattern using the back of a card or some other thick stuff Draw a circle on the back of your card or cardstock etc. The size of the circle is up to you. The larger the circle, the larger each face of your "dice" or polyhedron.
begin with a dot on the circle

You are going to need to inscribe an equilateral (all sides the same length) triangle inside the circle.

To do this, keep the compass locked open to the same radius you used above and draw a single starting point on the circle.

Keep the compass open to the same radius. Now with the compass point seated on that starting dot, use the compass to mark off equal increments around the circle.
Keep working your way around. Simply mark your way around the circle. You will eventually reach your original starting dot.
Six equally spaced marks. You will have six equally spaced marks.
Draw your triangle now.

Now connect every other mark with your straight edge and you will have created an inscribed equilateral triangle into the circle.

*We will be using the circle pattern first, and then we will cut out the triangle and use it as a pattern.

Be sure to keep both the circle and the leftover. Here we cut out the circle pattern. Be sure to keep the leftover frame. We will use it as a viewfinder to select the best spot to cut out of our cards.
using the "viewfinder". It really helps to be able to move the viewfinder around and find the best place to draw the circle.
Lay solid pattern over spot and trace. Lay your solid circle pattern over the spot you've selected and trace the circle.
Voila! Cut out the circle and you are on your way to a really cool 3-d figure.
The no. of faces on your "dice" determines the no. of circles you will need.

You will need to cut out a circle for each face, or side, of the polyhedron you are making.

  • tetrahedron = 4 circles
  • octahedron = 8 circles
  • cube = 6 circles*
  • icosahderon = 20 circles
  • dodecahedron = 12 circles**

* The cube will need to have a square inscribed into each circle instead of a triangle.

** The dodecahedron will need to have a regular pentagon inscribed into each circle.

Now cut out the triangle pattern. Now it is time to cut out the triangle pattern.
Trace on the back of the card circle. To create the flaps for connecting our figure, we will be tracing the triangle pattern onto the back of each circle.
Be SURE to SCORE the triangle!

RED ALERT: this step is vital!

Be sure to use your straight edge and the ball point pen to go over very firmly each side of this triangle you just traced.

This is known as "scoring" and it will give you a perfect fold, because the pressure of the pen starts the crease of your fold.

See how sharp those folds are!

All you will need to do is lightly press the scored flaps up.

*NOTE: if you fold them up as in this demonstration, your polyhedron will be quite decorative with the flaps showing on the outside.

We thank Mrs. Barbara Townsend for this design activity.

If you would rather have a smooth outer skin with no flaps showing, we recommend folding them down and using glue instead of staples to attach the flaps.

Be sure you are alligned before you staple. We always check the back for proper alignment before we staple or glue.
Start stapling.

We are going to make the above icosahedron. So start stapling flaps. Usually one or two staples placed close to the fold line will do the trick.

If you want a firmer, more rigid bond, we recommend white glue. Remember however that this will greatly increase your construction time, as you will have to wait for the glue to dry.

Five tringles stapled for the top. Here you see five triangles stapled together into a pentagonal "top" of our icosahedron.
Five more makes the bottom. Do the same for the bottom.
Here is what they look like underneath. Here is an underside view. We are now ready to make the middle with the remaining 10 triangles.
The middle goes together like this. Staple or glue them together like this.
Bottom connected to the middle, ready for top. Here is what it looks like with the bottom connected to the middle. All it needs is the top to finish it off!

We thank Mrs. Barbara Townsend for this design activity.

Here is the finished product. Click the image for a larger view.

Please note that all of the platonic solids can be made in this manner.

Click HERE if you want to see the patterns for the others.

This is full of ready to make dazzling polyhedra. Cut and Assemble 3-D Geometrical Shapes...
We highly recommend this cut and assemble book. These figures are sturdy and very brightly colored. They will last for years and rotate gracefully when hung from a ceiling. Usually ships in 24 hours.

 

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