3 hours
It's finally time to put the last skin on this wing! I wrangled the forward skin back on the wing again, and went at it.
I did the row along the main spar on both sides first, then the upper flush rivets, and the lower flush rivets last.
As soon as I started on the upper flush rivets, I had several of the rivet stems break off proud of the surface. I was surprised because I drilled all the holes with a #32 drill instead of #30 prior to dimpling, and I did several tests on scrap material that came out perfectly. My only theory as that my in-out deburr tool must have enlarged some of the holes a tiny bit. I ended up with about 25 rivet stems sticking out, and two that pulled completely through without breaking (out of about 77 total). After a few rivets with the pneumatic puller, I switched to one of my manual pullers. It seemed to mess up less rivets but who knows. It definitely took longer!
I was able to tap most of the stems back in with a punch, and the rest I very carefully ground down with a Dremel grinding wheel. The two that pulled through, I just drilled out and replaced.
Bizarrely, when I did the lower rivets every single one came out perfect. I drilled, dimpled, and deburred the top and bottom exactly the same so I have no idea why! But it's done now anyway!
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