Fuselage - Bulkheads

2005-01-23 - Assembling the F-704 bulkhead. (4.0 Hrs).

I started out match-drilling the F-704C/D parts to the F-704A/B center sections. Unfortunately, I realized that there are 4 more close-tolerance bolts per side. These are the NAS1304-50 bolts (i.e., AN4 close-tolerance). So, I checked to see how they fit, and, surprise, surprise, they were way too tight, also. I know, I know, these are supposed to be tight, but as I said before, the vertical piece of the center section that is riveted to the two thick bars does not line-up exactly with the bars. Using a magnified light, I could see a slight offset from the holes in the bars.

Anyway, I spent a fair amount of time making sure that at least two bolts would fit in all of the holes. Again, I used a deburring tool on all of the -4 holes, just like the big -7 holes.

Drilling the left F-704G. This is a thick piece of AL. I used a new drill, but it really didn't make much difference. I even used the electric drill instead of the battery powered drill.
Both F-704Gs, all drilled and countersunk.
Here's where I figured out that I needed to work the -4 close-tolerance holes and bolts, just like the -7 holes.
Everything fits.
One F-704C drilled and deburred.
Ouch, that's sore.
I got two saw horses, today. Hopefully, I'm gonna need these pretty soon. I know, you're saying "can't he even make a couple of saw horses?" What can I say, these were $4.99 a piece from Harbor Freight--they hold 350 lbs. I can't buy four 2x4s for $10. And, they fold up. Can't pass up a good deal.