Today I attempted to remove the remaining rivet pieces from the left fuel tank.  First I used the borescope and was able to locate a few more, then I sloshed water to no avail.  Finally I removed the last remaining rivets to the z-brackets. 

Today’s primary task was to remove the sealant around the previous fuel tank baffle. Removing proseal isn’t fun, and requires a fair amount of sweat to accomplish.  I did a fair amount of research on the forums in advance and here are my tips for removing proseal.

• Purchase some tough plastic scrapers like the ones pictured below from harbor freight.  They’ll allow you to scrape the proseal without scratching the aluminum. Additionally, you can easily resharpen the plastic with the scotchbrite wheel.  Sharp edges help substantially.
• Next you can use a combination of scotchbrite pads, heat, MEK, and the scrapers to continuously work down the remaining sealant.  I personally didn’t use heat as I found it too time consuming for such a large sealant removal job.  I did use scotchbrite and MEK.
• A couple iterations of scraper – MEK – scotchbrite seems to do the trick!

Here are the tools I bought at Harbor Freight. The scrapers are for the proseal removal. The pneumatic angle grinder and sanding discs are for the wing skin scarf joints. Here is a “before picture” of the baffle proseal.And a picture after the first round of scraping.After the first scotchbrite / MEK run….And the final product!

Installing the baffle isn’t terribly difficult, nor is it a lengthy project.  Which means this tank is almost complete… for the second time!

Getting these blasted rivets out of the tanks is proving to be far more difficult than I had anticipated, and I was expecting it to be difficult. I bought at USB “borescope” camera off of Amazon for $18.  Its a cheap bit of junk but it serves its purpose.  With this camera I was able to remove many other rivets.  Next I tried sloshing water.  This brought out a few more rivets, but at final count I was still short.  Finally, I gave up and drilled the baffle off of the right tank.  Drilling rivets was easy.  Removing pro-seal was not.  I destroyed the baffle in the process and had to order a new one from Van’s.  I’m now 5 rivets short of having them all.  I’m not going to remove the other baffle as I’m convinced I can get the remaining five with a combination of the camera, magnets, and sloshing water.

I attached the camera to one of the telescoping handles I have for an inspection mirror.  Then I affixed a piece of string to the very end so that I could manipulate the angle of the camera inside the tanks.  It worked very well.  Lighting was a bit difficult with the high reflectivity of the aluminum.

Here’s how I’m keeping track of the rivets as I remove them.  

Here is the tank after I removed the baffle.

The proseal I will need to deal with prior to installing the new baffle.  Not going to be fun. 

Here are some interior pictures I took with the USB camera.