The task was certainly interesting, it takes some artistic ability and finese...physically a little strenuous, but not too bad once you get the hang of it. Its a very rewarding process, as you feel pretty good about yourself when you get done and the curve matches pretty much exactly with the print. And let me add...its not too bad when you have a set of longeron bending dies to use (once again, big thanks Sean Blair!). Those babies were pretty handy, I think it would be much more time consuming without them...doing it the way Van's describes in the instructions. Essentially they will bend the longerons to the prescribed RV curve. It took me a little while to really understand the process but after I did, it was a piece of cake. The whole process probably took me about 2 hrs total, but if I were to do another set, it would be an hour, tops.
Now that this is out of the way, along with my bulkhead assemblies, things are really about to get exciting. The next step is putting the rear fuselage (tailcone) together. From there, it should be no time before I have a 'canoe' to sit in! I've been waiting for this point in the project with a lot of excitement and anticipation. :)
Bulkheads riveted together, pretty straightforward and done with the rivet squeezer so its a piece of cake. Just pay attention to the many drawing callouts to leave rivets out until later and make sure you get your empennage attachment bars (center bulkhead) on the correct side of the bulkhead. Also note, the aft bulkead (left) has -426 rivets flush on the aft side.
This is the rear baggage bulkhead-it separates the baggage compartment from the tailcone. Notice several places will be riveted later in the fuse assembly, that's why you see cleco's.
Aft bulkheads...
Now for the longerons, first step...cut 'em to length, then remove material from the aft end (see above) as specified in the plans.
Do a good layout, mark the top, sides and critical locations for the curved section. You dont want to bend these suckers in the wrong orientation. I cut out and taped my template directly to the table, no sense in making an elaborate template as Van's suggests. I also added index marks every two inches for reference. Although, in hindsight, I would increase this to every 3" as the bending dies are 6" long so shifting them half the distance--3" every time seemed to work out nice when I did the second one. I think 2" is overkill for what you are trying to achieve.
This is what the bending dies look like, with instructions. A couple things I found helpful. First they are very tight when the angle alum are inserted for bending. I had a hellluva time getting them off after the first few attempts. I then sprayed some WD-40 on them to act as a sort of release agent...that helped quite a bit. Second, it takes a lot of force on the vice to get a full bend...I used a soft mallet to get it snugged down. Third, I recommend going to a full set on your bend. The first one I kept trying small increments of bend to 'sneak' up on the required curve, afraid to overbend it. The dies are designed with the correct curve...trust it and and just bend them full tilt on the first try, no need to sneak up on it as I don't think you can overbend them with these dies. Needless to say, the second one I did in this fashion took me about a half hour total...much quicker. And lastly, I got really close to the prescribed bend with the dies but then just clamped the angle to the table and tweaked it ever so slightly by hand to get the last little bit of bend in there. As you can see, I think they came out pretty nice...does it look like the profile of a fuselage??
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