Believe it or not, but you can build a clock with wooden cogs. Lorna bought me the building pack from ROKR puzzles: https://rokrpuzzles.com/product/rokr-pendulum-clock-3d-puzzle/ You start by putting all the gears together and than add them one by one to the clock frame. A bit of wax on the anchor esacapement and winding up the spring does the rest.

The finished product actually runs quite well.