Another hour-and-a-half saw me more or less finishing the gimbal unit. I put the first coat of varnish on the plywood.
You’ll notice that there are two pieces of plywood – an upright piece for supporting the gimbal frame, and a horizontal piece for retaining the former. Both are hinged - the upright one to the gimbal frame and the horizontal one to the base of the upright one.
Because the pieces are hinged together the unit can be folded to occupy less space, and it can be stowed forward of the cabin or in the lazarette. Setting it up takes but a few seconds, and it can be attached to the port or starboard sides of the cabin. If used when the boat is underway, the starboard side will be better than the port, because there it will be clear of the halyard, topping lift and furling line. When the boat is at anchor, the unit can be placed by the main vent.
I believe the unit will work well, but I shall not know for sure until I try it when the boat is sailing.
I’ll have a go at making a chart table that will fit on top of the unit where it will be very convenient for doing chart work.