Fuel tank assembly complete

The tank comes mostly assembled, with a few finishing items not yet done.

The first task was to remove the tanks, which was easy but time-consuming (lots of screws and bolts):
Tank removed from the right wing
riveting the bearing:
Bearing riveted to right tank
I installed the skin nutplates, including those that are only called for much later in section 44 (didn't find a reason not to):
Nutplates riveted to right tank
I bent and cut the fuel sender arms, only to find that I, like others, had screwed up and cut it too short without realizing the arm is supposed to go through the sender. Ordered new arms, re-did it - correctly this time:
Fuel sender arms after bending

Fuel senders, VA-261 pickups, drain and other hardware for the tank
I read up a little more on the fuel system and realized that, if I decide to use a FADEC, I may need a fuel return line. Much easier to do it before installing the tank, so I did some careful planning - some people from VAF pointed out that it can't be too far aft or it'll get in the way of the wing attachment. I got two more VA-141 brackets for this, and used a 3/8" NPT tap to make sure I could screw VA-261s in from the other side. I then used those to drill the holes on the side of the tank, next to the vent line:
Holes drilled for fuel return line bracket on left tank
We did the drilling with a vacuum cleaner extension (piece of conduit taped to the tip of the vacuum) strategically placed to catch aluminum bits, which greatly minimized the mess inside the tank, but we still had to later move that extension around to clean up all the bits that flew around the tank.

When I drilled the left one, I realized I, too, had made a small mistake - notice the J-channel from the tank's structure shows through the hole - the hole was too close to it, so I had to shave off the corner of the J-channel to ensure the VA-261 would still fit.

On the second tank, I drilled the hole a bit further to the side, and instead trimmed the bracket itself to fit, this time hitting no obstacles inside:
Holes for fuel return line bracket
Trimmed VA-141 bracket for fuel return line
Finally, I installed the senders, return bracket, pickup, and drain, using tank sealant and thread-locking sealant. For the fuel return brackets, I used CR3212-4-2 rivets:
Fuel return bracket, fuel level sender and fuel pickup installed on left tank

Fuel return bracket, fuel level sender, fuel pickup and drain installed on left tank

Right fuel tank with all plugs and brackets installed
We then installed the Newton fuel caps - even in the garage, the Van's caps were annoying enough to open and close to make me want to replace them:

Cleaning the excess sealant from the fuel cap bracket the best we could

Newton fuel cap installed (needs some cleanup afterwards)
Last but not least, someone at VAF called my attention to the fact that I hadn't left a ring terminal around one of the fuel sender screws, so after the sealant cured I checked the ground continuity between the fuel sender plate and the skin, and it seems to be conducting just fine.

Among the next steps are leak-checking the tanks and reattaching them to the wing spars.

Time lapse:

Total fuel tank time: 12.1h
Total fuel tank rivets: 30

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