Today I started work on adding a skin stiffener to the upper end of the rudder, which is similar to the elevator skin stiffeners.
The picture below is a diagram of where this doubler is located.
The details for this doubler were provided to me by Mark Frederick and I started with doing some basic layout and pattern making using a file folder because it is made from some good rigid paper stock.
I transferred the paper template onto aluminum and cut out the doubler blank and bent a flange as required.
In this next picture you can see how I did some layout and head scratching on the outer surface of the rudder skin.
Once I got the pattern made, I cut out the piece of aluminum and as you can see, my doubler closely resembles the example that Mark provided from his latest project. Since the rivet patterns between his F1 rudder and my RV-8 rudder are different, I had to tweak my doubler slightly to make it work.
Here is a picture of the doubler blank clecoed in place.
I then cut out the lightening hole and will need to make the flange around the hole.
When I located the doubler on the rudder skin. This picture doesn’t show much but you can see that I started by drilling locating holes in the ends on one side, using the existing rivet holes. Additional rivets will be added between these existing holes.
After getting the pilot holes drilled on the spar and rib sides of the doubler, I then used the rivet spacing fan to evenly space the rivets on the diagonal side.
Here is a picture of the doubler in place prior to the final drilling.
Once the rivet holes on the diagonal side are drilled, I put the doubler back on the skin and back drilled all the holes to the skin.
Here is a picture showing the skin doublers on both sides of the rudder skin. Again, this mod make a noticeable difference in the rigidity of the rudder with very little weight added.
Please comment, I love to hear from my readers. Thanks again for coming along for this ride, you make my work worthwhile.