were you ultimately successful? I have just started making these objects. Lets share notes.

Which model are you working on at the moment Reeja? My most recent was a compound of 15 cuboids in a rhombicosidodecahedron.

It's a sort of truncated stellation of the Rhombic Triacontahedron.

http ...

Just to observe that the third one can be worked out easily without trig as it consists of 4 pentagonal pyramids and two pentagonal antiprisms with the pentagons paired so that their vertices coincide with alternate vertices of their circumscribing decagons.

I would tackle the second one by drawing ...

Great!

Pleased to see that you are completing the edges of the decagrams!

I think if I were making this one I'd use 10 colours for the triangles and 6 colours for the decagrams, so 16 in total.

Keep up the good work.

Hi Eric!

My first bible was Mathematical Models by Dr H. Martyn Cundy & A.P. Rollett. My second was Uniform Polyhedra by H.S.M. Coxeter, Dr J.C.P. Miller & M.S. Longuet-Higgins.

Way back then I used to sit and look bewildered at the drawings of the non-convex snub polyhedra.

History is repeating ...

I didn't use any.

I try to avoid using internal bracing. It is essential for 5 Cubes, but all the others have proven to be rigid.

Have to admit that 10 Tetrahedra is a big disappointment. Lots of lovely colour, but the shape is a bit too much boring dodecahedral.

It's not a proper compound by my ...

I've answered it myself!

I'm 11/12 of the way there, and it's getting pretty rigid.

The dart shaped facets are divided down the middle as you are using two colours for each.

Presumably you are double-tabbing, so the dart shaped facets will effectively be hinged down their middle.

How does this affect the overall rigidity of the model? Did you need to use any internal bracing?

What materials do you use?

Those look superb!

I would be nervous about using hinges if only because in time the cement would cause the card that I use to distort.

Maybe this is because balsa cement is a tad powerful?

--.

There is a picture of mine on Facebook. It is completely rigid and very near perfect.

My Small Stellated Dodecahedron likewise has no internal reinforcement and is rigid.

You have to be VERY accurate, and very patient as you hold each vertex / re-entrant vertex until the cement sets and all hint ...

Ensure that you close any gaps at all 12 vertices and at all 20 re-entrant vertices.

The polyhedron should then be completely rigid and not need any internal reinforcement.

Vive le difference!

I didn't realise Stella could "do" this one.

It is quite amusing seeing all the data correct to umpteen decimal places.

I divided the 360 degrees into 14, and used a couple of spring bow compasses to produce the net for the equatorial pentagons - not measuring any dimensions ...