Fuel Tanks 22 (6.0 hrs)


I made a major mistake this weekend, but before I get to that, let me provide a run down on my progress and technique.  Each session started by sealing the flop tubes, vent line and fuel sender bnc connection. For sealing the baffles, I essentially followed the technique given by Van’s.  With a few minor alterations.  In addition to the bead of sealant on the tank skin forward of the rivets, I also put a very thin layer of sealant on the baffle flanges and the flanges of the outer ribs.  I’m sorry I didn’t take many pictures during the process.  I didn’t want to get sealant on my camera which doubles as my iPhone.

I ran out of rivets so I contacted Mike who had some spares.  I met him at the hangar and used his tap kit to tap my tie down brackets while I was there.  If I had only known then the mistake that was already in progress…

After this weekend in the shop, I’m solidly convinced that I’m mildly retarded.  Or dyslexic. Or maybe both.  I managed to put the right z-brackets on the left tank and vice versa.  I did all of this despite all of the brackets and tanks and wings being labeled.  Heck, I even labeled the posts that make up the wing stand.  To make matters worse, I even checked that I was putting the correct brackets on the correct tank.  The only explanation I can muster is that my mind read what I was thinking and not what I was seeing.  So now I’m left with the unenviable task of drilling out all the z-brackets, replacing the rivets, and cleaning the interior of the tanks.

When I first realized my mistake, I was crestfallen.  I looked like a cat wearing a sweater. Frozen in my own misfortune. In that instant, I could have thrown the whole project in the trash.  After a little while to calm down I realized the mistake might not be as bad as I initially thought.  At the point where I realized the mistake, I had not completed installing all of the z-brackets on the second tank.  After some thought, I decided to finish installing them.  There was a chance, small though it was, that everything would line up and I’d be able to install the tanks without a repair.  Additionally, since the sealant was already applied, I thought that continuing gave me the greatest chance for the remainder of the baffle to be properly sealed.

Unfortunately, the tanks did not line up.  Again, I was crestfallen.  I sent a message to Mike Bullock… so he could get a laugh and share in my misery and I could regain my sanity.  He found a thread on VAF detailing someone else who had made the same mistake.  I should be able to drill out the rivets and repair without any other removal required.  I was afraid the entire baffle would need to be removed, which would have been a huge undertaking.

Now, I’m glad that I continued.  While this leaves me more to drill out, I’m confident that both baffles stand a good chance of a proper seal if I can make the repair appropriately. Removing the baffle would have been a nightmare.

Initially I was going to put an order in to Aircraft Spruce, but the rivets I need are on backorder.  So it looks like I’m going to have to get them from Van’s.  While I’m at it, I’ll probably talk to their tech support just to get another dose of sanity.

My last action for the weekend was to clean as much sealant off as possible in order to make the repairs easier.  I’m hoping to remove the rivets tonight before the sealant properly sets… fingers crossed.

Here are the completed tie-downs:20140309-210802.jpg

Installed z-brackets.  Wrong z-brackets that is…20140309-210810.jpg

The spray on primer doesn’t stand up to acetone at all!  Here is where I cleaned off the proseal in preparation for drilling out. 20140309-210819.jpg

I even have the posts labeled. 20140309-210832.jpg

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And the brackets.  Yeah, I know… stupid.  Mike said I’d earned a new callsign.  “Tanker” Great. 20140309-211044.jpg

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