Before being able to predrill the rear roof skin, I had to finish the positioning and drilling of the different sections of the cabin side false ribs. There is nothing in the assembly manual and very little detail in the drawings of this part of the construction and I have spent many hours looking at other web sites and going over the drawings etc. In order to ensure that the finished false rib profile matches up with the completed wing (something that I haven't started on as yet), I postioned the components , clamped in place, used a strip of aluminium to form the leading edge, then measured the chord of the rib. This is supposed to be 1590mm and it turned out just about spot on, so I then had to decide where to position the rivets holding the forward and rear sections.
