[sdiy] solid geometry

[Tim Stinchcombe]

Hi John,

> I want to mount the speakers evenly distributed on the 
> sphere. What is the formula for doing this?
> 
> I have found formulas for dodecahedrons and icosahedrons but 
> they describe 12 and 20 flat surface solids.

I'm pretty certain that if you want them 'evenly spaced' then it can't be
done with 25. I would stick with either the 20 (icosahedron), or get 7 more
speakers and do it like a football, which is made from 20 hexagons and 12
pentagons, so 32 faces (it is after all an icosahedron with the points
chopped off). I don't know how 'regular' the centres of the faces would turn
out to be, but I'll bet its good enough for what you want.

Google on 'Platonic solids' and 'Buckminster Fuller', and I expect that
buried in there somewhere you'll find lots numbers and formulae.

Tim

__________________________________________________________
Tim Stinchcombe 

Cheltenham, Glos, UK
email: tim102 at tstinchcombe.freeserve.co.uk