Eyestalk pivot...

The pivot is made from two pieces of MDF. This one is slightly thinner
than it should be, but this is to allow for the addition of 1.5mm aluminium sheet facing.

The threaded tube runs all the way through the pivot. The two nuts in the foreground will be
glued into the sides. They will be used to attach the pivot to the brackets inside the dome.

Although this is a 1960s-style eyestalk, I've given the pivot a flat front because
I prefer this 'look' and it also allows the tube to mate up with the pivot more effectively.