Fuel Tank T-901 & T-902

Hey everyone.. my own self quality control discovered a problem. And you may have guessed it, I'm sure this has happened before.

History: I was out of town for several years. I returned a few months ago, moved and setup the new work shop. And of course I picked up where I left off.

Problem: I have dimpled the T-901 skin along the T-902 Baffle on the Right Tank. So when I return, I did exactly the same thing on the other tank. Naturally I dimpled the skin, so I counter-sunk the T-902 (on both Left & Right).

As I was about to seal up the tank this evening, I was looking for the rivet size and well 'By George' it say 426-3.5....DO NOT Dimple T-901 or Countersink T-902. ERR.. Yeah, I did both!

Is this a serious problem? The skin and baffle seal up nice and tight. Or will it be a fitting problem to the wing?

Looking for thoughts on this before I call Van's in the morning.

Thanks!
-Allen

...Kicking myself, I feel like I have made any progress in 3 years, and now I'm thinking I need to start the tanks over from scratch again.

Maybe OK

Allen,

I think the reason they suggest countersink and not dimple is so the 902 baffle will slide into place easier when you're sealing-up the tank. If you can manage doing that with the dimpled skin and baffle then you should be OK (maybe a second set of hands).

Your other option would be to flatten out the dimples with a squeezer and then countersink the tank skins per plans. I would check with Vans on that one.

Tom

Since I posted the problem, thought it'd be kind to share the outcome.

I so spoke with Ken this morning. Good news is this booboo only cause additional steps to the fuel tank (Counter sinking the T-902). Ken also mention that the baffle may prove a bit more difficult to line the holes up. (No problems there, hole line up perfectly).

This weekend, I seal up the tanks.

I did the same thing on my build, turns out to be a non-event. It's only slightly more difficult to fit the baffle during sealing, not a big deal. You'll get messy doing it but you can get it done.

Test fit the pieces and mask off the skins with tape. The tape will help you avoid/mitigate the huge mess that will happen when you have to push in the rear tank baffle down between the tank skins and they are all buttered up with proseal. It is tight, but you should be alright to leave the dimples on the tank skins. Van's makes it sound like you will never get the baffle in if the dimples are there. There is plenty of give to the tank skins and they can be pushed out enough to slide the rear baffle in. Don't skimp with the proseal! Most leaks seem to happen at the rear baffle edges.