Fuselage Center Section #2

 Continued working on the main center section of the fuselage.

Cleco'ed the aft bulkhead to the main center section channel.

Match reamed all the holes that are common with the main channel.

Deburred the holes in the main channel.

Found a mistake made by the factory.  There are 6 extra holes drilled in the main channel.  Support says to build on with the option to fill these with flush rivets. 

Deburred the match drilled holes in the aft bulkhead.

Marked specific holes in the main channel that get machine countersunk.

Countersinking complete.

The KAI gives a specific tolerance for the width of the wide part of the countersink.

And last thing for today was to machine countersink these holes, one on each side for a flush pulled rivet.  Used the 120° cutter for these.