Got a lot done in a fairly short amount of time tonight. I got all the rudder stiffeners back riveted in. They are shot in with a method called back riveting. That’s where you put the “manufactured head” of the rivet (the big end that sticks out) on a plate in your table top, and hammer down the back side with the rivet gun. The huge advantage of this is since you don’t work the visible part of the rivet, they all come out looking PERFECT!
I also got to use a technique I saw on the EAAVideo.org site for rivets in tight quarters. Check it out here. This is the only way I could get the last rivet in the lower rib without purchasing a “No Hole” yoke for my squeezer for another $125.
After riveting all the stiffiners on the rudder skins, and riveting on the upper and lower ribs, I set to making a custom back rivet plate that will be used to form the trailing edge of the rudder. It’s just a piece of 2×2 angle iron that is bolted onto my bench, but it becomes a perfectly straight surface that you can cleco the rudder to as it’s formed. This leads to your rudder being perfectly straight as well which is the whole point! It was pretty straight forward with two minor hitches. First, I had a piece of round molding on the edge of my old main workbench. This has worked great for years to keep small parts from rolling off the bench top. But since I needed a smooth transition from the bench top to the angle iron, it had to go. It was getting pretty beat up anyways… so no big loss.
The second catch was that while the rudder needs to sit flat against the bench while it’s worked, there are two “horns” that stick out past the skins on either side. These horns will eventually have cables attached to them and they are what will move the rudder back and forth when in the air. So to get the skins to lay flat, I had to cut a slot into the bench top for the horns to fit thru. Again no big deal, because the masonite bench top surface I have is getting old and beat up, and after this project, it’ll get replaced with a new piece.
The result of the efforts are is a perfectly straight back rivet plate. Hopefully it all goes together smoothly when I start adding the proseal!
And tonight’s video: