From the moment I heard that the Zenith design included using a small bungee inside the rear fuselage to separate and create tension for the elevator cables, I knew I would be doing something different. Many before me have divorced the two and cut the steel elevator horn off of the torque tube and mounted it independently so that it doesn't turn when moving the stick from left to right. IMO the divorce and resulting design is a much better method and more in line with modern avaition. Perhaps the old design works, but it's not for me.
So the first thing is to figure out how YOU will do it...many have come up with various alternatives. I have taken the best from what I have seen others do and improved the design. I have made all the critical pieces out of 4130 steel. Not sure why Zenith makes the horn out of aluminum when all the other controls on the plane are made out of steel. I made mine from steel and just copied the aluminum piece. The original horn was mounted on a 5/16th tube. I chose to use 3/8" with a .125 wall. I beefed up the sides of the tunnel where the device will mount by adding a piece of .040 on each side. Two things I didn't like about some of the other divorce designs I've seen. 1. There was no additional support on the shaft across the tunnel (about 6 3/4"). 2. The horn rotated metal to metal on the new shaft. To solve the metal to metal I added a 3/8" ID Oilite Bushing. To solve the distance support issue I used two pieces of rectangular extrusion (aluminum), 1 1/2" by 3", on each side of the tunnel. This reduced the distance in the middle that had no support to approximately 3 3/4". I also added about a 1/2" joggle on each end of the horn to keep the cables from touching where they cross inside the fuselage (Toatl distance side to side of about 3/4"). Here are the parts, more to come.
