For the front upper rack I used 10x3mm styrene. Had to glue 2 of them together to make the framing 10x6mm with a over hang of 10x3x10mm. Did that for both sides. Rounded off the over hang and drilled a hole in it at 5x5mm in. Did the same with the back part of the rack but in reverse so they would slide together making a hinge. To make the hinge work I cut a hollow piece of 5x5mm styrene for a cross member. Cut 10x6mm styrene for the rest of the cross members. When gluing together I layed down wax paper and butted each corner up to a T square. Once dry I slid in the hollow 5x5 into place and cut a piece of hanger to make the hinge functional.