Here's the scope built for my Dad. It's an 8" f/6 built around a Discovery mirror and secondary. They work very well.

The scope rotates in the cradle and moves to and fro for balance. It is very light for a sonotube model, if I remember right it's under 30lbs. The sides and bottom of the rocker box are built of 1" plywood. The structure is very stiff, but because of the cutouts it's light as well.

I'm really happy with how this scope turned out. It moves smooth because the big alt. bearings are closer to the diameter of the az bearing. The mirror cools fast due to the open "T" design mirror cell. I'm sure my Dad would rather have this scope than one that looks like my 8". Waitng for some optics!