Initial Prep and Prime
8/22/23 - 0.6h
8/23/23 - 1.2h
The aileron trim servo connects to the control system using a couple springs attached from the aileron trim arm to small brackets attached to the torque tube-to-bellcrank pushrod. I separated the trim spring brackets with a hack saw, cleaned up the cut edge with a file, and then deburred the edges and holes on each bracket. Priming the trim spring brackets was also straight--forward and relatively quick with my well-practiced process.
[Hole and Edge Deburring Tools, Hack Saw, Files, Grey Scotchbrite Pads, Bon-Ami Cleanser, Dupli-Color Degreaser, Rust-Oleum Automotive Self Etching Primer (Green – Rattle Can)]

Assemble
8/25/23 - 0.9h
The real trick to this step is locating the trim spring brackets and assembling the system. The first step is to mark the centerline of the trim arm, and then transfer that line to the pushrod while the pushrod is in its neutral position. I used the neutral template for the bellcrank to position the pushrod and hold it in place. I then attached the trim servo assembly to the spar with clecos through the wing access panel attached to the trim servo. This is one instance where it is helpful to have access to the interior of the wing without the bottom skins in place. If the skins were attached, there would be no way to see the centerline of the trim arm to transfer that location to the pushrod. Given unencumbered access to the wing interior, I had room to use a laser line to find the trim arm centerline location on the pushrod.

Another benefit of doing this step prior to attaching the bottom wing skins is the installation can be completed without removing the pushrod. Once the centerline was marked, I used 6” strips of tape to locate the edges of the trim brackets, and I used the laser to find the centerline of the pushrod to align the brackets. From there a couple taps from the center punch located the first hole for each bracket. I match-drilled the brackets to the pushrod, and then riveted the brackets in place.

The final step prior to attaching the wings to the fuselage is to test fit everything. The springs are insanely tight, but I got the springs attached to the trim arm and the spring brackets after a lot of time and effort. After attaching the springs, I cleco'd the trim assembly back to the wing, and noted that the springs held the pushrod in the neutral position. I struggled to disconnect the springs after completing the test fit, and discovered that I could use my duck-billed pliers to open up the end coil slightly to make the spring easier to connect and disconnect. I inserted the pliers inside the connection coil for the trim arm, and then opened the pliers to provide enough clearance to remove the spring. I plan to leave the springs permanently connected to the spring brackets, and I'll squeeze the connection coil shut after I reinstall the trim assembly for the final time.
[Laser, Center Punch, #30 Drill, Rivet Puller, Duck-Billed Pliers]