Almost finished is something you never want to say in this project. You may often feel “almost finished” but I assure you that you are not.
A thorough inspection of our work revealed several areas of concern. First and foremost the cherry rivets that are called for in the bottom longerons where the box meets the engine mounts need to be removed. I found it very easy to drill out these cherry rivets as they are flush head and the pins can just be punched out and then drill out the mass of the rest of the rivet with a #31 drill bit (these are CR3212-4-5's. The dome head ones that we used on the inside would require you to grind off the head before being able to punch out the mandrel. However since these are flush rivet sets and the heads broke off the mandrels before they were fully set.
I did wonder why they used these cherry rivets instead of solid rivets and then when you inspect the back you realize that the heads of the inside cherry rivets (that are 5's) are in the way. So using the cherry rivets will be easier and since they are structural there's no problem using the pop rivets here. (Assuming they set correctly).
After we fixed those we noticed that the after fairings were not laying flat and there were not a lot of fluting options to make it both line up with the holes in the skins and match the curvature of the side skins. There was really not way to make it perfect (though we tried!). After several adjustments and a little “un-fluting “ with the hand seamer I managed to get it to lay relatively flat agains the skins and the holes lined up decent enough to make me feel comfortable with the fit, not a lot of stress on the clecos.
After we finished those off and riveted them to the skins we added the remaining nut plates. Then we re-installed the after wing attach bars )which were literally the first part you make in this fuselage kit!) and we realized that the holes in the skins were not quite big enough. A little filling and sanding and we were back in business. We added some alodine to the skin surface to help avoid corrosion.
Next it is onto the bottom skins. Incredibly difficult to get the bucking bar inside the longerons flange and over the head of the rivet. It took finding just the right bucking bar to do it (picture below). The final rivet is a AN426-4-6 rivet but the bolts in the way and it's impossible to get there and also not crack the rivet head due to the longerons flange and so we decided to stop and order a cherry rivet for that rivet.
Lastly, I am including a picture of the whiteboard I have dedicated to keeping track of all the things that I am missing and need to finish up. It's a beast to try and keep track of all the things that need to be finished and it's a great idea to write them down. Previously I had been making notes in my plans and then crossing them off when I got back to them. This make it a lot better and keeps these tasks in the front of my thoughts so I remember to finish these various tasks.
An example is the bottom row of rivets for the battery box. There's nothing urgent about finishing these but I simple could not set these without a 7.5” off set flush head for my rivet gun. I finally got this and now just need Ted to come back as this would be hard to do alone. So it's still on the board!
Oh, I also prepped and primed the parts for section 30! That's where we join the aft fuselage with the main fuselage. No will need to remove my tail feathers and re-arrange some things but it's gone be great!