F-776 center skin question.

[bret]

I am doing a 7A and getting ready to asemble the center section. can some one chime in about the five outer forward holes. they say to countersink the aft skin of F-772 here, for duble flush head rivets, do I not dimple or CS these on the F-776 skin, and CS the top of the bottom flange of the outer forward holes of the F-704 ? there are also 4 spots for the stiffner angles?
Also I placed the gear leg weldment into position and it looks like there (would) be enough room for normal shop heads here? and..... it looks like we scalop the flange of F-704 bottom flange for the gear leg to clear? sorry for the long post. Don't want to buy any more parts....Thanks, Bret.

 

[rzbill]

Bret,

You are correct that some of the spar carrythrough flange has to be trimmed away to make room for the "A" gear trunnions. Go at it carefully and you can minimize the material removed. If memory serves, I lost a couple of rivet holes in that area even with minimum removal.

In regards to the double flush rivets, I did not do that (in this case it is because I forgot), but I was fortunate that the gear trunions fit fine with normal shop heads in that area. I can't say if that is the case for all weldments.