As I get close to ending the shaping of the plywood pieces the next step has been to begin glueing some of the ply pieces together. The process began with cutting, shaping and trimming the ply pieces, shaping the capstrip and spruce reinforcement parts, then glueing them together to make the pieces that will be used on assembly of the centre section. Pics below show glueing the double thickness trailing ribs of the centre section and the method I have used to ensure the front and rear faces of the 4 ribs of the centre section are square.