Empennage

I got back from Africa last Thursday night and have spent the last few days with the family. I've also gotten reacquainted with my C150 by flying over 3 hours in these six days since I've been home. Today I got out in the garage to finish the work on the rudder. From the last post you know that I had the trailing edge glued and cleco'd to a piece of heavy aluminum angle before I went back to work last month. It seemed to have set up well and looked very straight. I went all over town this morning trying to find a piece of 3/16" steel about 5' long and 4" wide to use as a backplate to rivet against. I finally got a tip that the only place in town with that was the Farmer's Co-Op. When I got back home with it I used my grinding wheel to smooth all the edges. The instructions indicate that keeping the trailing edge straight is pretty difficult. You have to use a technique called 'double-flush'. These are standard rivets but instead of setting the shop head on a flat surface, it is set in a dimple and ends up flush with the skin surface. The factory flush head ends up almost perfectly flat, but the shop head, though flush with the skin doesn't fill the dimple completely.

I back-riveted the trailing edge rivets as per the instructions. I did about every 8th rivet and only set it about halfway. I worked back and forth until I had all of them set about half way. Then I flipped the rudder over and set the trailing edge rivets with a mushroom set. After I had set all of the rivets I turned the rudder over again and used some finesse to make sure all the rivets were completely set. I was able to keep the edge from bowing and all the rivets turned out pretty well and smooth.

The next step today was to form the leading edge of the rudder. Had to make another trip to the hardware store to get a piece of 3/4" steel pipe to work with. This turned out to be fairly easy and didn't take too long. I followed the instructions in Section 5 of the plans and used the pipe with a bunch of duct tape. Once I got the pipe taped to the rudder I just rotated the pipe to form the curve required. Then I turned it over and did the other side. All the pre-punched holes lined up nicely and I cleco'd them together. I final drilled all the holes and deburred the edges that I could see. All there are put together with blind rivets and and was easy to accomplish.

So that does it for the rudder and it's in the stack with the Horizontal Stabilizer and the Vertical Stabilizer now. Next up is building the elevators.

3 Hours

Total hours on project = 107