Fitting the F-775 Rear top skin - 5.5 hours

 The F-775 rear top skin was ready to go on. I managed to get the top/middle of the skin cleco'd on just fine. however getting the holes to line up on the bulkheads as they get closer to the longerons was not easy. Looks like I will need to flute more on the bulkheads. Since things were lining up well at the top, I match drilled the J-Stiffeners.

I then used masking tape to make note of which areas needed more fluting. It took me a few tries to get it all lined up and cleco'd 

 

Next I placed a straight edge across the bulkhead which would allow me to set the final placement of the F-656 gusset plates. Once I had the gussets clamped, I removed the top skin and then drilled the #30 holes.

I noticed that the fit of the F-786A J-stiffener with the F-708 bulkhead wasn't great. I needs a little trimming to clear the flange. I checked the fit and took measurements, verifying that the area of interference was much less than the dimensions shown on Drawing #18. I trimmed the Stiffener just enough to clear the flange.

The top skin was ready to go back on, but still seems like minor adjustments are still required.