2/4/2007
I started on the center bulkhead F-704 today. This bulkhead was shipped to me with the wings last year because it is the part of the fuselage that the wings attach to. This section is a matched set to the wing spars. They've been in this plastic bag under the guest room bed for a year!
Here's all the parts that were in that bag. I love gooooold!
The instructions have you start this part by drilling out several holes for snap bushings. I did this, as most do, with a Unibit. Some of them are prepunched in their locations, but the ones in the middle for some wiring and trim cable, are not.
After that, I cleco'd everything together to drill the rivet holes out. There is a forward section (on top) and the aft section.
In order to make sure all the holes are drilled PRECISELY, the NAS bolts are brought out of their hiding place and placed thru the holes (not too far though) to keep everything PERFECT. This is essential! Only one is needed on top and one on the bottom since the holes use these close tolerance bolts. They fit VERY TIGHT! I used a little air tool oil before inserting them to make egress a bit easier.
The F-704G sheer bars also need to be in place for drilling. These are held in place temporarily with an arbitrary AN4 bolt that is long enough. They also get clamped in place since there are no nuts on the bolts.
After drilling the holes to #30, I disassembled everything to deburr the holes. And here we are, right back where we started!
3.25 hours