If I were to model this ( and I'm not because I could not do this as well as it was done) I would have used a 2D laser cutter/engraver for a lot of the Flat sections that would have been cut faster such as the arch form structure and the windows. The rest of the details that could not be made as flat cuts with the 3D printer making parts with back-pegs to fit slots cut into the 2D pieces.
The 3D printer makes parts so precise that fitting pieces together can be made extremely tight as Carl has made them.
Great piece of work.
