Wing - Left Fuel Tank

2004-02-29 - Fitting the tank skins. (3.0 Hrs).

I wasn't going to work on the tanks today, but I went out to the garage and things just started happening. The good news is that I was able to assemble the left tank and cleco it to the wing spar, drill the W-423 Joint Plate, and everything lined-up perfectly. Again, Van's instructions work just fine. I did have a few minor problems with the instructions, but nothing major.

Here was the first problem with Van's instructions. They say to cleco the tank ribs to the baffle while the baffle is attached to the spar and match-drill each T-712/Baffle/Rib. First, it is impossible to cleco the last rib to the baffle unless you remove the leading edge assembly. Second, it is very hard to drill the ribs while attached to the spar. It is a lot easier to just match-drill the baffle to the T-712 brackets, and then remove the baffle and match-drill it to the ribs.
Here was the next problem with Van's instructions. They say to cleco the skin to the ribs while the ribs are attached to the baffle and spar. I spent nearly an hour trying to do this, and it is not possible. I got the bottom clecoed, and the end rib clecoed, but I could not get another cleco installed--the skin is just too stiff. I did see on someone's website a few days later where the builder actually used the sides of the wing cradle while the skins were on the wing. I think that was a little extreme (but inovative).
It's best to just remove the ribs and baffle, and cleco them together in the cradle. Even this is hard to do, and I didn't get clecos in both sides of all of the ribs. But I did get enough in so I could put the tank back on the spar.
After I put the tank back on the spar, I was able to drill the holes in the W-423 Joint Plate. Notice, that the gap is gone. The match is almost perfect! Van's way works, for the most part.

If the nose of the tank sticks out a little, just push an ice pick into the tank attach holes on the spar, and pull the tank skin down some before drilling the holes in the Joint Plate.

Tank temporarily attached.