Now that I’m basically done with the wings, I can go back to working on the fuse. Section 26 – Mid Fuse Ribs and Bottom Skins will be creating the back half of the fuselage floor. As this will take up some significant space, I wanted to make sure I finished up the left over little stuff on the wings.
Before I even started, I read through the chapter to ensure I understood the sequencing. I quickly realized that I have to do a few steps, prime a few parts, rivet those parts together, then do the next few steps. This repeats throughout the chapter vs most other sections where I can prime and rivet everything at the end. Lots of little primer sessions in my future!
First few steps, build the Inner and Outer seat rib subassemblies. Nothing new with these parts. Only thing I should have done was to fabricate and include the flap motor mount parts when I primed the subassemblies.
Next, I start pulling the parts for the rear seat ribs and fabricating the seat belt brackets for them. Before I cleco these ribs to the bulkhead, I need to rivet the previous brackets to together. TIP: Make sure you flute the outer most ribs to match the bottom skin. (F-1015L/R and F-1018L/R). These are really the only ribs that need to be fluted, and as others have found it’s quite difficult to flute them once they are riveted together.
Again, nothing hard, just cleco, match drill, deburr, prime, and reassemble. About now, things are starting to get big so I ended up getting one of those “cheap” work platforms from the big box stores. Another option would be to stack some 2/4’s on the ground as a platform as the bottom skin needs to hang down past the forward bulkhead a bit.
Only other “gotcha” or oops I had was that I didn’t check the alignment of the F-1018R rib with the fuselage bulkhead assembly and allowed the rib to be trapped inside the flange of the bulkhead assembly. It should have been on the outside of the bulkhead and I had already started to rivet things together. Not a major problem, but I’m not a fan of double work. Drilled out enough rivets to allow me to move the parts into the correct position. From there, all is great and I’m able to build on :).
Lastly I start to cleco the skins onto the ribs and bulkheads. This was really cool to see and starts to make me worried about space issues in my garage. For now I’m rolling with the punches, but things may get interesting in the next few sections. With such a large part, I decide that I’m going to mark every hole I drill to make sure I don’t miss anything. Makes match drilling go a little slower, but I’m ok with that.
UPDATE: 4/7/2020 – One thing not fully covered in the plans is where to put the MFG heads vs the Shop heads in this section. Only when I went to install the rear seat floor pans did I realize there may be a recommended method. Where possible, put the round MFG head on the passenger visible side. It not only looks better, but also makes it easier to install the floor later on.
NOTE: While not called out in the plans, I would HIGHLY recommend that you dimple the F-1015B and F-1015A #40 holes now to allow the side skins to sit flush once they are dimpled. While it can be done later, it’s a pain in the rump. See Plans page 29-15 and 29-17 for rivet callouts.