19.05.2021 Shutters aloft!

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Wednesday 19th 51-56F bright start became overcast. Little of the promised sunshine. Which meant I had to do something other than imaging this morning.

First I fixed two sets of [3] arcs together to mock-up two, outer, shutter ribs. Though mostly only one thickness they are twice as deep as the finished article for stability. They were fine with a few screws between the overlapping sections. Then I slid the heavy and flexible, shutter strips up over the ribs. This is the closed shutter appearance.

As usual, I couldn't get far enough away for a full frontal shot. The prickly hedge is much too close.

There should really have been two centre ribs but I used only one for simplicity. This meant I had little control over the shutter placing and ended with an untidy overlap.

The messy arrangement at the top is shown in the image [left.] The two shutters should [and will] meet edge to edge. With closure boards to fix to the drawer slides.

Note how the shutters follow the curvature of the dome for a nice, low, wind profile. This is with 100mm [4"] deep ribs. I might reduce this. Provided I can get a seal between the outer shutter ribs and the observation slit ribs when the shutters are closed. Only the rib depth above the dome will remain. The section below the dome will go.

The view from the inside the dome [right.] With a wide angle lens setting and my head jammed against the back of the dome.

The GRP appears much darker, to my eyes, than in this image. 

I am using a sturdy stepladder to brace the centre rib, using a vertical plank and several G-cramps. Otherwise it is completely unstable laterally. I still need to make another central, shutter rib and the slit ribs. Though I wanted to do a mock-up of the shutters and tie ribs before making any decisions.

With the shutters closed I can keep the rain out. It promptly rained at 12.30 and later.

 

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