Got all of the bulkheads riveted. Mostly good work on my part, however I had two outcomes that will result in a lighter wallet.
First they get cleco'd up.
Then they get nailed together.
Horizontal stabilizer front attach bulkhead. All rivets squeezed. I actually had to remove and replace the two top rivets on the right attach bar. On one I mangled the shop head by being off center with the squeezer and the other somehow got a rivet that was 1 mm too short.
Horizontal stabilizer front attach bulkhead. All rivets squeezed. I actually had to remove and replace the two top rivets on the right attach bar. On one I mangled the shop head by being off center with the squeezer and the other somehow got a rivet that was 1 mm too short.
Bulkhead with tail tiedown. All rivets squeezed. Notice the slight warping of the holes near the #12 screw holes in the bracket. This was due to my dimpling those holes (per plans) only to realize that they should not be dimpled so I had to flatten them (plans need a revision on 10-07, step 1). I also dimpled each hole in the web the wrong direction and had to re-dimple in the right direction. Update 11-Dec-14: I've decided to replace this bulkhead even though it's already riveted in. Update 29-Jun-15: The bulkhead was replaced after installation in the aft empennage.
Horizontal stabilizer rear attach bulkhead. All rivets squeezed.
Aft bulkhead with rudder cable bracket. I used the rivet gun to prevent warping such thin parts with the squeezer.
Forward bulkhead. Again, I used the rivet gun to prevent warping such thin parts with the squeezer.
So now, the big mistakes.
Mistake #1: I took the picture on the left to be manifested in the physical world as on the right. How could that happen? See, I got overconfident on recently finding several rivet sizes in the plans that were inaccurate and decided the AN470AD4-4s called out should be -6s. Proud of myself for finding another error in the plans, I later found that I was the one in error, but only after squeezing 19 rivets.
I decided I could drill out those 19 rivets to separate the parts and move on. Which I did. The holes were slightly enlarged, but not too badly. However in the end, I decided that I didn't want that part in the plane with the stress introduced by my error. So I'm going to replace those parts. The battery angle is $17. We'll see what the ribs are. I'm awash in surplus nutplates so I don't need to purchase any more of those. I'm actually solving two issues at once since I also had a countersink too deep on one of the battery angle nutplate attach rivets.
Also, the plans don't call for the bellcrank rib flanges to be dimpled #40. They need to be as they will be directly riveted to the skin.
Mistake #2: On the systems bulkhead, I dimpled not just the nutplate attach holes (the latter highlighted in red), but the screwholes too. Not a big deal really. I pressed them out, but because dimpling stretches the metal (especially for #8 screw holes), the part was no longer very planar. Looking at it, I didn't want it in the plane, so I scrapped it and will replace it. Also, whilst working on this bulkhead, I found out I was missing MS21055-L3 (a.k.a. K3000-3) nutplates. Apparently, I'm not the only one. Wasn't even on my manifest.
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