I built the central plinth, consisting of the wider angled sections underneath and a hexagonal core which came up to the level of the collar around the time rotor. This provided a foot-wide ledge on which to sit the control panels.

The control panels form a hexagonal ring that sits on the ledge. It’s built in two halves that are bolted together.

The pieces of the inner core (the hexagon containing the actual time rotor) are a tall plywood hexagonal tube. I used a table saw to cut the plywood with 30-degree angles along the edges so that it would form a proper hexagon in cross-section. I then cut a large hexagon from a plywood sheet and cut a hexagonal hole in that with the outer dimensions of the hexagonal tube.

I also cut a hexagonal base and used 2x2s to anchor the hexagonal tube to the base. The top of the hexagonal tube is held together by the hexagon with the hole, which fits over the hexagonal tube. This sits on top of six pillars cut from 2x8 wood.

This central time rotor core is very sturdy – I’ve stood on it to reach things high up.

The whole thing is nearly completely covered with bathroom board, which makes it smooth and white without painting. The black panels are matt-black sprayed bathroom panel. I cut square holes behind every other black panel for access - I didn't cut every one because I thought this would weaken the structure too much. Three of the panels are thus removable. All the edges are clad in aluminium sheet which is folded in a workbench against wooden formers. This doesn't produce perfectly sharp edges, but is good enough. I cut the aluminium with heavy duty tin snips.

If I was doing this project again, I'd split the plinth in two halves vertically as it currently won't go through most doorways.