Update on 6 year old Akzo Nobel Primer and on to the next LE Challenge

I am happy to report that the 6 year old Akzo Nobel primer that I used the other day to prime several parts, including two of the LE ribs, seems to have worked just fine. There is no flaking or chipping, and adhesion to the metal seems to be just fine. So I think I can continue to use that $200.00 investment until it runs out. Good to know.

Now for the next challenge. As I previously reported, I can still remount the LE again and final drill the two rear rib flange holes, but before I do that I wanted to start the process of trimming down the subskin to its final form. I had this pretty much figured out until I encountered the next challenge:

What to do about the existing service hole that was pre-cut from the factory on the bottom of the left wing LE. the right side does not have this cut, and that is because the original plans located this hole for installing and servicing the stall warning kit. To further complicate matters, the access panel that is designed by SafeAir for allowing installation and access to the auxiliary fuel tank transfer pump is located in a slightly different location. Part of this location overlaps the location of the existing hole that Vans already cut into the skin. Each of these access areas requires installation of a backing plate/stiffener to serve as a mounting flange for each in inspection plate. Here is the pic that kind of lays this all out:

The unfinished parts are the access panel and mounting flange from the SafeAir kit, and the blue colored flange and access panel that overlaps the SafeAir panel are the ones from Vans. Almost immediately you can see the problems. The Vans access panel is more to the rear of the skin, closer to the wing spar. The SafeAir location is more forward (the flange is not in the correct location, which is where the unfinished cover plate is. I just wanted to separate them so that you can see that they are two separate parts. You can also see the size difference.

Since I decided not to use the Vans stall warning system, opting for an AOA solution instead, I would really rather use the SafeAir kit. But how do I get rid of the existing hole that Vans made, and then re-cut a new one to fit the  SafeAir kit? As you can see, I will have to cut out part of the existing hole, but not all of it.

To complicate matters even further, my subskin currently resides where either of these mounting flanges would need to be installed. This may actually turn out to be a blessing because I may be able to  use the existing subskin as the mounting flange for the new panel, and it will also serve as the mounting flange for the existing panel that will need to be permanently mounted, except for that small area that overlaps the hole for the panel of the SafeAir kit. Then there is the fact that the skin thickness of the SafeAir panels is thicker than the .025 LE skins.My caliper shows them to be about .0315 inches thick. My guess is that they were cut this way because this kit is designed for several different Vans aircraft models, including the RV-10, so they may be thicker because of that.

I purchased the Safe Air panels because even if I choose not to install their aux tanks right away, it will be nice to have these panels already installed, in addition to the bung kit on the fuel tank, so that all I will really need to deal with is the actual installation of the aux tanks and the transfer pump, and the hose fittings between the main and the aux fuel tanks and the transfer pump. So the more I do now the less work I have to do later.

Not only that, but I like the larger, and more centrally placed location of the SafeAir panel. A long time ago I tried to fit my arm and hand inside the smaller panel that Vans provides, and there just isn't much room for either. I could imagine having a very difficult time troubleshooting fuel leaks in this area or servicing the transfer pump.

So basically, I need to cover up the current hole and cut a new hole. I'll have to think on this one a bit to get the sequence of the steps down correctly, but I think I can do this smartly by using the subskin for the mounting flanges. Luckily, the right LE skin does not have this mess of an existing access hole, so all I have to do on that side is cut the hole for the SafeAir panel in the bottom of the right wing LE skin.

Did I mention that I will be glad when all the LE work is done, so that I can start on the fuel tanks again..... It just never ends. Whhhhhaaaattt????? Did I just admit that I am looking forward to working on my fuel tanks??? I must be crazy.

KPR.