I built a new 10x12 ' split pitched roof observatory a year and a half back, to replace a smaller single roll off observatory that was no longer adaptable for my needs. The roof splits and rolls off north/south, I utilized redwood frame members for the roof because of the lighter weight vs doug fir, external roof and wall of metal, metal wall studs with interior of plywood paneling, each side loaded on low riding 4x 4 wheel (smooth ball bearing) sets, riding in garage door channel struts, supported by welded piers . I absolutely love the results. It takes very little effort to roll out the roofs.
The roofs are locked in the channel struts, so NO unscheduled lift offs
, and as you've noted, I can leave either roof opened or closed. In my specific location, there is wind protection west and east, but north is entirely open and south is partially open to wind gusts. I've operated the observatory in 20 mph winds from the north and south with the appropriate roof closed, in complete protection. The observatory houses two different systems - based on two Byers Series II GEM ; on one mount I have a 16" RC with a smaller WO refractor atop, and the other the 11" RASA and a larger WO refractor atop that. I have two computers inboard, one for each setup.
BW
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