Sealing the Fuel Tanks – Part I

Today I started to seal the left wing fuel tank.  I decided to follow the method laid out by Rick Galati at Van’s Air Force.

The method involves fay sealing surfaces and allowing the sealant to partially cure before riveting.  It is supposed to be less messy, and after handling the sealant for a while, I can imagine that trying to shoot rivets with this wet material everywhere would be quite frustrating and sloppy.  I masked off the area around the stiffeners to allow for easier clean-up after a partial cure.  We’ll see how that works out tomorrow.

As it was, the method is (so far) not terribly messy, as long as you’re willing to sacrifice a ton of nitrile gloves to prevent spreading the sealant around too much.

Today I prepped and sealed the left wing tank inboard rib hardware (fuel flange and anti-rotation plates) and five of the fourteen tank skin stiffeners.  I could have done more, but had only mixed 55g of the sealant (50g Part A : 5g Part B).  That was just exactly enough for the pieces I worked on today.  Perhaps I could have been a little less generous at first and got another stiffener or maybe two, but it looks like you need about 10-11g of sealant for each stiffener, including losses to the pot and gloves, etc.

When I opened the can, my first thought was:  “Wow, that’s a polysulfide!”  And sure enough, it is, according to the manufacturer.  It has a rather rich aroma.

Here’s what I accomplished today.  More tomorrow.

The inboard rib hardware:

The stiffeners: