Brief Description: Attach Ribs to Main Spar (Left)
Attached the rear ribs to the left main spar today. The hardest part was "joggling" the rib leading edge top and bottom flanges to fit inside the top and bottom flanges on the main spar. This involved holding a small section of 2 x 4 inside the rib flange in such a way that I could tap an indentation into the rib (using a rubber mallet) to match the space needed to slide each rib in between the spar flanges. It took a while to get the hang of it, but seemed to turn out okay.
Ribs #1 and #4 were an additional challenge in that the rivet line on the forward side of the main spar was blocked by a structural piece. Normally, the rib flanges are drilled out by sighting a reference line on the flange through the pilot holes on the spar and using those pilot holes to guide the drill bit This arrangement required me to find a way to blind drill through the rib flange into the existing holes in the spar. I did this by marking out extension lines for each pilot hole in the spar and transferred those lines to the rib flange. Then I had to drill the pilot holes into the rib flange using a 90 degree angle drill attachment since a regular drill wouldn''t fit into the tight space. This method worked out well, but it wasn't fun trying to figure it out.
So all nine left rear ribs have been attached to the main spar. Tomorrow I attach the rear channel to the back of the ribs.
RR#1 placed over the top of the highlighted main spar pilot holes
Drilled and clecoed RR#1. After much fretting, this worked out fine.
All 9 rear ribs clecoed to the main spar with the rear channel clamped to the aft end of the ribs.
