CD Dome

CDs are widely used by ISPs to distribute their internet access software. They are subsidised to the point where they are available free of charge.

So: here's a dome made out of CDs and plastic cable ties:

CD dome - from the front

Quite a few of the CDs are AOL "Shrek 2" CDs. A few spare CDs of this type can be seen scattered around the dome.

There are also a range of old magazine cover discs, scratched CDs, obsolete CDRs and coasters.

CD Dome - from the top

This structure is a tensegrity. It consists of a mixture of structural components and tension only components - and the tension components are critical to the overall structural integrity.

I've never come across any tensegrity structures made using circular structural elements before - so as far as I know this is a somewhat novel structure.

The dome - from the inside

Transparent CDR "endpiece" CDs are used to form a window - and this is visible on the inside view - at the top.

The CDs in the model are "shingled" - in an attempt to keep out the rain. However the holes in the centres of the CDs are too large for this to be terribly effective.

This is a small CD dome - and the high curvature stresses the CDs - and quite a few were broken while making this dome.

Significantly larger CD domes along these lines should be possible - and hopefully they will not suffer so much from the bending stresses that are present in this small model.

I strongly suspect that my construction only scratches the surface of the tensegrity models that are possible using CDs and string.

While I don't yet have any concrete designs, I suspect it may be possible to construct Snelson- style "floating compression" structures from these components - without making grooves in the edges of the CDs - by a process involving wrapping the string around the CD and passing it through its hole.

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