Shutter slides rethink 2: Upper guide rollers:

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I have had time to think over the options for skate wheel slides.

Mounting the support slides at the top would put all the loads on the dome at the worst possible point. The top of the dome has the 1m wide cutout for the observation slit. Despite being framed by the ribs and zenith boards I prefer the shutter loads to be taken by the combined, fourteen, rotation rollers under the base ring.

The vertical guide rollers at the top will sandwich the shutter top boards. These upper guide rollers will be on the outer edges of the shutters. At the strongest point of the ribs. Channel stops will catch the shutters and hold them firm both when open and closed.

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