Hi!
People asked several times for more details, so here we go...
In the beginning you see the vertical tube, pivoting around. The tube of 50 mm is supported by a ball bearing. It is held in a vertical position in an outside tube of 60 mm. The gap between the two tubes was an issue, I cut a 50 mm PVC pipe open in length, and pushed it in the gap between the tubes.
Of course, the drive shaft has to be in the center of the tubes, to allow the pivoting movement without stressing the drive shaft when moving up-
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