3.0 Hours -
Although it feels like I’ve been working on these fuel tanks forever, the end is in sight. Closing the left tank definitely felt like a milestone!
I started the day by deburring the edges of the left tank baffle. This was pretty easy and only took a quick pass on the Scotchbrite wheel. After the deburring, I thoroughly cleaned the baffle with MEK and then prepared a batch of tank sealant.
As with the right tank, I used about 110 grams of sealant for the baffle. However, for this tank, I used a little more sealant for the skin/baffle joint, and I placed the bead of sealant over the rivet line instead of on the forward edge of the rivets. Hopefully, this will prevent the leaks that occurred on the right tank (I still need to retest the right tank as well).
Once all the sealant was in place, I lowered the baffle, lined up all the holes, and then clecoed everything together. To rivet the baffle, I started by squeezing all of the skin to baffle rivets, then I installed the rivets and z-brackets for the outboard and inboard ribs, then I installed all the pop rivets and z-brackets for the interior ribs. For some reason, the pop rivets seemed much more difficult to install this time around. Oh well, they all went in eventually!
Sealed and clecoed, the left tank baffle is ready to rivet.
Another view of the left tank baffle.
Finally, I cleaned up the tank a bit, and then mixed up another small batch of sealant just to do some touch-up work. I could have used the sealant that I had left from the first batch, but it was starting to get a little rubbery and difficult to work with.
Once everything was finished and cleaned, I sat the tank vertically on the bench with the baffle/z-brackets facing down. It probably won’t do anything, but maybe gravity will help ensure that the skin to baffle bead of sealant is constant.
The key parts of this picture are that the z-brackets are on and the tank is finally out of the cradle.
Hopefully, I’m almost done with the tanks and working with sealant. In another week, I’ll test the left tank and retest the right. With any luck, my fuel tank building days will be behind me and I can, finally, move on to something else!
Soaking my clecos in MEK for awhile should make it easier to clean the sealant off of them.
