More Fuel Tank Sealing

Well today Dad and I delved into sealing ribs in the left fuel tank. In our previous work session we got the stiffeners, fuel tank filler, and fuel drain sealed and riveted into the left tank. Today we wanted to catch the right tank up to this stage so we got to work on that. While our rivets soaked in an M.E.K. bath in our Starbucks Expresso bottle we got prepared to rivet. We followed the same procedures that we used on the left tank except for one exception. Instead of using -4 lenght rivets for the drain, we went down to -3.5s. Reason for this is that the -4s were too long and tended to "lay over". We're not going to worry about this though since the drain is a non structural component and it's battered up with a good amount of sealant (which is also a strong adhesive).

Once we caught the right tank up we moved on to riveting the interior ribs for the left tank. This proved to be more difficult than the stiffeners since you're working in a more confined area. We put the skin in our cradle and clecoed in all of the ribs minus the one that we would be working on. This is recommended so the fuel tank stays straight and maintains its shape. We mixed up our sealant and got to smearing! Before we did though we scored the flange (and previously the skin) with emory cloth to provide a prime adhesion surface, once we were done with this we made sure to put a thick layer of sealant along the whole flange of the rib. Once it had a good layer we slid it in and put a cleco in every hole to pull it tight. Our riveting process had us rivet the front half of the bottom of the skin, then the full row of rivets on the top, and then finish the remaing half of bottom rivets. Van's tells you to rivet from front to back in order to eliminate slack.

We were able to finish two ribs today which made us happy! They are definitely a lot of work and we shall get back to work on Thursday.