With the bulkheads now complete, it's time to start assembling the fuselage. This is a really exciting part as the 3D shape of the plane really starts coming together quickly.
This part starts with bending the longerons, which are a couple of angles that run from the front of the plane all the way to the rear. These start as 15+ foot long straight aluminum angles that need to be carefully and accurately shaped with a gradual bend along a portion of the length, a sharp bend at another spot, plus a twist along the front end. I proceeded very slowly and carefully, not so much because it's difficult, but rather the cost of shipping long replacement parts would cost quite a bit.
After the longerons, the rest of the aft fuselage looks like it will come together rather quickly, as it's simply taking the bulkheads that are already finished and attaching the skins to it. The main key is trying to make sure there is no twist in the fuselage, but this is unlikely to be a problem with how accurately the prepunched holes in the kit are.
Total Construction Time: 55 hours
April 6, 2007 (4 hours)
I started bending the first longeron today. I spent a lot of time carefully measuring and remeasuring my bend and cut marks along the length. Next I cut the two angles to the proper length. Finally I started the first gradual bend. I found the paper templates Van's provides a good initial guide, but you need to use the radiused edge of the aft deck to get the bends just right. Van's method of clamping the angle in a vise, pre-bending a bit with your hand, then whacking the angle with a rubber mallet works quite well. By repeating this, moving the angle about an inch in the vise each time, you can get a really nice bend. The main challenge is that whenever you bend in one direction, the angle also bends in another direction, so you need to correct this using the same method just in the other direction.
April 7, 2007 (4 hours)
Today I went a lot faster getting the gradual bend in the second longeron. I laid one on top of the other and the two match very well. Next I made the sharp bend down that's about 28" from the forward end of the angle. Here the angles really want to bend in the other direction quite a bit, and when you correct it throws of your other bend. This becomes a bit of an iterative process. I compared the final bend to the side skins which I placed vertically but upside down on the table. I was able to get a very good match. Finally the forward 28" of angle gets twisted 17° inward. By keeping the part clamped in the vise, grabbing the front end of the angle with a wrench and twisting, you can get a pretty accurate twist.
April 8, 2007 (1 hour)
It's Easter today and we had guests most of the day. I did manage to sneak out for about an hour and drilled the rivet holes from the aft canopy decks through the longerons.
April 9, 2007 (1 hour)
In the morning before work I trimmed the aft ends of the longerons where the last bulkhead attaches.
April 14, 2007 (4 hours)
Today was one of those rewarding days where your progress really shows. I spent some time in the morning finishing up some bulkhead work. Later I built some saw horses for the aft fuselage. I then fitted the two rear bulkheads to the tailcone skin. Making these fit right and getting the rivet holes to align takes some work, but I finally got a pretty good fit. Next I cut and trimmed the J-stringers to length. I then assembled the bulkheads to the bottom skin and next added the side skins. I realized I need to do some additional trimming to both ends of the J-stringers when I tried to fit the tailcone skin/bulkhead assembly. Either way, it's really starting to look like an airplane!
April 15, 2007 (1 hour)
Trimmed the forward ends of the J-stringers. This is one area where the plans leave you guessing, but once you start assembling it becomes clear.
April 16, 2007 (1 hour)
Attached the rear bulkhead/skin assembly and found that on one side of the F-711 bulkhead the spacing between the vertical rows of rivets of the bulkhead halves don't match the skin rivet spacing. The right spacing is 20/32", but the bulkhead spacing is 22/32". Spent some time playing with ideas to solve.
April 17, 2007 (1 hour)
Found out that the rivet spacing issue is a common one. Finally I removed the bulkhead from the assembly and rebent the flanges to get the right gap. Now it fits right. I also leveled the whole aft fuselage in preparation for match drilling using both the plumb bob method as well as a level across the skins.
April 18, 2007 (2 hours)
Spent a couple of hours in the evening match drilling the skins along and through the J-stiffeners. This was pretty easy until I got to the aft skin where it meets up to the side skins. The bow of the bottom skin makes it really tough to get the holes aligned.
April 19, 2007 (1 hour)
Finished match drilling the skins and bulkheads today. I was a little worried that I might have elongated some of the rivet holes where the aft skins come together, but while some were slightly enlarged, all seemed within spec.
April 20, 2007 (1 hour)
This morning I disassembled the aft fuselage assembly and then began deburring the j-stiffener rivet holes. Upon disassembly I found that about three or four of the aft skin holes were a bit more elongated than I like. Debating how I want to resolve.
April 22, 2007 (3 hours)
Finished deburring the j-stiffener rivet holes. I was debating whether to remove the plastic along the rivet lines or the whole skins. Decided to break out the soldering iron and just do along the rivet lines. I also got a start deburring the rivet holes in the bottom and aft skins.
April 23, 2007 (2 hours)
You guessed it...more deburring. Finished all the rivet holes, then the edges of two of the j-stiffeners and the tail cone skin. Should easily finish the rest tomorrow, then it's on to dimpling.
April 25, 2007 (2 hours)
Finished up the j-stiffeners and then decided to dimple them using Pete's pneumatic squeezer.
April 26, 2007 (1 hour)
Deburred the aft bottom skin and miscellaneous other stuff.
April 27, 2007 (1 hour)
Deburred one of the side skins in the morning before work.
April 28, 2007 (5 hours)
Spent the morning finishing up the last bit of deburring, then dimpled all the aft fuselage parts. For the three or four elongated holes there is plenty of edge distance so I decided to drill out to #30 which solved the problem.
April 29, 2007 (7 hours)
It was a really nice day today so I started prepping the aft fuselage parts for priming first thing this morning. Once done I kept working and primed all the parts. Later on I decided to reassemble the whole aft fuselage and now I'm ready to start riveting.
April 30, 2007 (2 hours)
Started riveted the aft fuselage. The two aft bulkheads are pretty tough to rivet, and I ended up drilling out and replacing a few. I got as far as the bottom rivets up to the lower J-stiffener for the rear three bulkheads. I'll need to get Tracy to help buck the rest of the rivets on the bottom.
May 2, 2007 (6 hours)
Tracy and I spent quite a bit of time riveting the aft fuselage. All that's left are some of the rivets in the tail area and bulkheads. Once again Tracy did a great job with the rivet gun. I also took a picture of how I braced the tail to prevent any twist in the fuselage.
May 3, 2007 (2 hours)
Drilled out about six of the rivets where the tailcone skin, side skins and J-stiffeners intersect. I had accidentally shot too short of a rivet before I realized that the heads were pretty flat. Later I bucked new rivets plus quite a few of the remaining ones in the tail area.
May 4, 2007 (3 hours)
Finished all the rest of the aft fuselage rivets!!!
