From the construction manual it was not clear what the rivet orientation would be, after consulting other builder blogs and TAF I could rivet the parts.
Rib 2 should be riveted so that the tail is on the inside of the flap, for this I used the 4,8×15 mm rivets.
Nose rib 2 is too thin for 15 mm rivets, here I used the shorter 10 mm rivets, since the rivets are not visible from the outside I placed the rivets so that the head is on the thinner piece and the tail on the thicker piece.
Rivet flap ribs 2
