9.10.2021

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Saturday 9th 45F.

Yesterday's imaging interrupted progress on the base ring. I had laid out the base ring arcs across the shutter area/arched doorway. Then realized that I needed to chop off the bottoms of the shutter ribs too. 

The sun, as a cold white disk. Through cloud and thick mist. [Lumix G9, 400mm MFT.]

The arcs pass through them though not completely. A small margin of the outer edge of the ribs would not be affected. Though I doubt it matters. There is not enough rib material left for useful strength. There might also be clearance issues with opening and closing the shutters.

I had marked the bottoms of the shutter ribs for cutting off. Then realized the shutters were not supported in their final position. Unless they were suspended from the drawer slides, at their tops, then the shutters were much too low. Which would mean that the bottoms of the shutter ribs would end up at "half mast." 

The shutters are also heavily loaded at the bottom. So would need to be properly supported on more stacks of timber off-cuts. Worse, the geometry of the shutters changes with their height. As they are lifted the angle at the base does not remain the same. This is due to vertical rotation of the shutters around the dome centre of radius. Which depends on the exact location of the shutters' top boards.    

So I need to lift the shutters into a better simulation of their top location. Then arrive at a suitable height for the bottoms which allows for equal, shutter rib clearance from the slit ribs along their entire length. 

I can't fit the drawer slides with the covers still on the shutter ribs. Access is all but impossible. Or, I have to fit the drawer slides to the shutters first. Then hold the shutters open in their precise location. While I attach the slides to the dome's zenith board. Talk about Catch 22! 

In the end I decided to cut off the outer shutter ribs.

Imaging in the afternoon. Thin high cloud made the sky white again. Any initial clarity became unchanging smudge.

 

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