7.01.2022 Shutter top roller options?

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Friday 7th 35-37F, cold, windy and cloudy with early rain. 

 The image shows the geometrical problems of fitting rollers to the tops of the shutters. Here the  top drawer slides are still fitted. Note that the shutters are spherical. Which severely limits my options due to a lack of space.

 The orange disks suggest skate wheels rolling in an [invisible] channel. Though this raises serious problems of clearance with the outer ribs. The channel would literally have to penetrate the outer ribs as the shutters close. Precisely at the point where reinforcement of the shutter's top, outside corners is absolutely vital. [Red arrows.]

 Yesterday I was struggling to open and close the shutters on the 3m/10' plywood dome. It was a timely reminder! Such problems are the last thing I need on the new dome shutters. Not once everything is unreachable perched up high on the observatory building.

 SNIP paragraphs of meandering verbosity! What if I arrange the wheels and channel outboard of the top shutter boards? Instead of trying to hide them. The support channel need no longer penetrate the shutters' outer ribs. [See second image with detail painted on]

I can bolt the sides of two more skate wheel bogies directly to the outside of the shutter top boards using extra long, 8mm axles. The skate wheel axles will then be properly supported from both sides by the sturdy bogie channel. Just as they are on the bogies at the bottoms of the shutters.

 A 2m long, exposed, aluminium channel, open face upwards, will rest on the top of the dome. Supported on outriggers at each extremity. These will be bolted through the dome segment, joint areas, for extra strength. Using countersunk screws to avoid blockages in the wheel tracks where they join the outriggers. 

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