This is what I did, Sorry about the pic but I only took one pic for Instagram. Its a threaded rod, With a hole tapped for the geared motor shaft. Also a hole for a set screw. A nut pressed inside a coupling and copper pipe and two end caps drill a hole in one of the end cap same size as the threaded rod. You will figure the rest out just from the pic. You can glue it together, not necessary to braze it, but brazing is best. I'm using 1/2 copper. If I could find brass I would use that instead, just a preference.
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