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Old 15-08-2021, 01:13 PM
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Eldest_Sibling (Alan)
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Join Date: May 2017
Location: Mid-South, U.S.
Posts: 136
This, the very first GEM, or German equatorial mount, on the planet, the Dorpat...

https://i.imgur.com/3fCQwZW.jpg

Then, the Yerkes GEM...

https://i.imgur.com/4zpIsAE.jpg

I think it's safe to say that neither one of those equatorial mounts contained plastic washers.

Of course, compared to those two, my own is most insignificant. But we do manage to do what we might.

I felt that it was best to separate the two axes, then to work on them one at a time...

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Firstly, the axes needed the factory glue-grease, high-viscosity, cleaned out, then the parts of each inspected, and sized-up for what was to come. I began with the RA-axis. Both axes have an aluminum lock-nut, disk-like, solid, that keeps the parts within from falling out and apart onto the floor...

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The one for the RA-axis has three set-screws. Those must be loosened, backed off, and before unscrewing the lock-nut...

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The two holes at the front of the nut, circled in green, are used to unscrew same. I made a tool for that, of oak and galvanised 4d nails...

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The set-screws of the lock-nut are accessed through this hole, and as the axis is slowly rotated, one screw at a time...

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It's off...

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We then see the first of the ball-bearing assemblies, which consists of the ball-bearing ring itself, with two enclosures...

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After removing the lock-nut and the ball-bearing assembly, the RA-axis may be taken apart.

Last edited by Eldest_Sibling; 15-08-2021 at 01:26 PM.
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