re: flat, light surfaces

Elliot, List,

In the woodworking literature this construction is known as "torsion
box". And is used in cheap hollow core interior doors as well...
A search on torsion box should lead to lots of info...

The interesting thing is that the interior joinery can be very poor.
The strength and flatness come from the glueline(s) holding the parts
in a rigid relationship, holding whatever alignment was originally
present.

Hope this helps.

Ballendo

>On the subject of making a flat, light weight working surface, you might
>think about the optical tables that are commonly made by Newport Corp and
>TMC. These have 1/8" thick SS skins separated by aluminum honeycomb, which
>is adhesively bonded to the outer skins. They work pretty well, and are
>much lighter for a given size and stiffness than other affordable tables

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