Fuel Tanks 4

Last day that dad’s in town so I’d better get a full day’s work out of him…

We started by riveting the stiffeners, drain flange, and fuel filler flange on the right wing. Then we put the left side back in the cradle and set up to rivet the ribs. This is the time that fuel tank construction gets serious. For each rivet, the process goes something like:
1. Remove Cleco
2. Clean out hole of excess sealant from the overnight set up
3. Apply small dab of sealant to the dimple
4. Insert rivet. It will sit in this bed of fresh sealant.
5. One person holds the bucking bar, the other drives the rivet.
6. Repeat about 30 times for each of the 5 inboard ribs.
7. Use a small brush and apply a dab of sealant to the newly formed shop head of each rivet.

Short version of the story is that we worked all day and finished the inboard ribs.

One of the inboard ribs
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Bottom of the fuel tank. You can see the vertical rows of rivets for the ribs and the horizontal rows for the stiffeners
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Fuel tank drain flange
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Inside of the fuel tank drain. You get a good look at the sealant applied to the rivet shop head.
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I’m very pleased with the progress we made over the past week. We worked nearly 30 hours (58 man hours) and made significant progress on the fuel tanks. Thanks for the help Dad!

Fuel Tanks 1

First of all, Vans changed the numbering of the sections so I’ll just stop using section numbers in the titles to avoid confusion.

We have started on the tanks. I have been putting it off for a while because I was intimidated by the pro-seal. After reading quite a bit online from builders logs and forums on =VAF=, I decided to go with the method described by Rick Galati in this thread.

Speaking of other builders sites, I want to point anyone to Jim Novak’s RV-8 build log. Dad and I visited Jim’s shop yesterday and I spent most of yesterday evening catching up with his build log. I’ve gotten behind on several things since G was born and Jim’s log is one of them but he does a very good and thorough job of documenting his work. I read his section on tanks twice last night and this morning before we started sealing the ribs. Rather than go through the details of the process here, read Rick’s thread above and start here on Jim’s log and read from there.

Freshly dimpled and prepared skin ready for ribs, sealant, and rivets…
IMG 3085

First sealing step is to proseal the fuel line fittings to the inboard rib. We applied a healthy (if not pretty) layer of pro seal to the mating surfaces then clecoed every hole. We’ll leave this set up over night and rivet it the next morning.
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and here is the completely riveted piece.
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Next step is to seal then rivet the tank stiffeners onto the lower portion of the skin. Since I neglected to take any pictures of this you’ll have to use your imagination but we layer a bead of sealant then 100% clecoed the stiffeners. They set up over night and we riveted them this morning.

Next we installed the inboard ribs in the tank skin. We did this by applying pro seal to the raying surface (mating surface) of the rib then 100% clecoed them into place starting at the nose and working our way back.
IMG 3087

After that, we used the pro seal that squeezed out plus some additional pro seal to make a fillet on the non flanged side of the rib. We’ll do more on the flange side after riveting but it seemed like it would just make a mess to do it now. You can see the fillet here.
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and here
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This is what the flange side of the ribs look like. You can see that pro seal has squeezed out from the raying surface but we’ll add another layer after the rivets go in. Better safe than sorry….
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We’re going to work on the right side tomorrow and probably rivet the left side Thursday.