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On the night of Sep 09/10, 2019, Stacey Davis noticed a problem when she opened the dome for one of the introductory astronomy lab classes: one of the wheels on which the dome slit rolls fell down from the roof! This is a possibly serious problem.
The dome is an Ash Dome with a diameter of about 16 feet, so probably the 16 foot, 6 inch model.
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The dome slit rides on tracks which are slightly outside the dome itself.
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On the inside of the dome, one can see the tracks. Wheels which run inside these tracks are attached to the moving dome slit with metal brackets. The system looks very much like those used in ordinary garage doors. (In the picture below, the dome and track are on the left, the slit and its bracket on the right)
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The dome slit rides on five or six wheels in each track. This picture shows the interior of the top of the dome. One the left is the motor which drives the slit up and down. At upper right is one of the brackets with attached wheel; at lower right is the spot from which the bracket fell. Note the two bolts sticking out of a small rectangular structure; I'll call it a "mounting box".
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Here's a closeup of that mounting box.
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The bracket and associated hardware -- wheel and axle -- were recovered by Stacey.
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The question is: how can we replace the wheel into the track? Perhaps these closeups of wheels which are still in place might help us to figure that out.
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