The cut edges are chamfered to a close edge and glued. On the inside I have taped and epoxied the joins, a strong basic geodesic box.
The raised edges are 1.5mm thick spruce, wood glued in place. The corners will need filler since I couldn't get another width to keep the same edge width on two sides. The square edges other hang to be sanded back and become a little thinner - I think this is as per the studio model but that is difficult to tell. The best referance comes from Lunadude and only a single referance dimension is shown.
I will skin with glass fibre tissue and epoxy, that will hide all sins, bits of filler and make a strong box that should resist delaminating or exposure to moisture / movement.