Well, I’ve deviated from the plans again. The plans say to drill this outside floor rib after the rest of the center section is riveted together. It’s an interesting rib in that it requires fluting to introduce a curve rather then fluting to straighten it as we’ve done with all ribs up to this point.
I had all the floors clecoed in and figured everything seems to be in a final position, except the front main spar, so, why not drill it now. I drilled the bottom first, and then one aft flange hole gets drilled to #19. Then the top, making sure the rib flange is outboard 0.32” from the floor skin.
Why? Because the 704 wing spar can't be located fore/aft or up/down until the side skin is clecoed on. The instructions have you drill the 715 forward flange without the side skin? Weird. I’m waiting to drill the forward flange of the 715 when I drill the side skin.
The bottom flange is fluted to follow a row of holes in the bottom skin. The top is fluted to follow the outside edge of the seat floor. This rib is totally un-drilled so you have to make sure you flute the top in-between the floor holes. The floor skin ends overlapping the rib flange will have to be trimmed a bit at the front and aft end to put the floor behind rib flange. No matter how much you flute this top rib, you will not be able it get the very front or aft ends of the rib flange outside the skin. Plus, it just looks like the skins need a bit a trimming. So, just trim the skin back a bit at the ends.
