In article ,
Jim Adney wrote:

On Tue, 14 Dec 2004 15:54:57 +1300 Lawrence D'Oliveiro
wrote:

In article ,
Jim Adney wrote:

On Sun, 12 Dec 2004 17:08:58 GMT Bill Janssen
wrote:

I have seen pieces of power cable for transmission lines that was hollow.

What did they do to keep the stranding from collapsing inward?

Why should it collapse inward?

Murphy's Law, perhaps?

A hollow circular arrangement, even helical, would only be an unstable
equilibrium. Any perturbation would cause it to collapse.

Tell that to your water pipes, your chimney, tubular car chassis
members, and all kinds of other hollow building components where
strength and lightness are both required.