> It is my opinion that there are very few materials that would be
> superior to wood as far as stability goes in maintaining allignment or
> in equalization of optics and tube materials in temperature.
Our society's 20" f/4 has a multi (12?) section wooden tube, mounted on a massive fork mount. Being f/4, it is EXTREMELY sensitive to miscollimation. The wood proved to be totaly inadequate. It shows enough motion (buckling?), whether thermally or humidity induced, that the scope is constanly out of allignment - almost unusable. We are now going to make a truss for it. In short, for smaller longish amateur scopes it migh be OK. For large, fast telescopes (or photographic instruments) - forget it.
Bratislav