Upper Tube Section
2014.09.20. Today I worked some on my upper tube assembly: I routed two rings out of 1/4″ maple plywood and glued them together for the upper ring, and part of the outer and all of the inner circle of the lower ring out of 3/4″ maple plywood. I also routed a 3/16″ groove in the lower ring and the upper ring in which will be inserted the “walls” of the tube for light protection.
2014 December 17. I did a slight rethinking of the UTA in light of my move from a truss system with poles to the trapezoids. It required a reworking of the UTA rings. On Tuesday and Wednesday of this week I assembled the UTA and put the focuser and spider in place. Overall alignment still has me worried. But we’ll see how things develop.
Rectangles of hard maple serve as braces connecting vertical slats to rings. The wood pieces are glued and screwed in place.
2014 12 24. To enclose the upper tube section for light protection, I’m using sheets of black foam (18″X12″, 3 mm thick) I got at an arts-and-crafts store down the street.