I didn't get too involved taking pics there because this was complicated. each hinge piece is beveled 22.5 degrees on each side for one end. On the other end, the bevel is 67.5 degrees for 1/3rd of the thickness, then 67.5 degrees for 2/3rd of the thickness for the other face. When jointed together, the tiny pieces in the corner lock them in place. This took a ton of trial and error and I'm glad I cut extra.