Brief Description: Trim Tab Motor - Installation, Calibration
Temporarily installed the Ray Allen electric pitch trim motor assembly into the left elevator. Clamped the trim tab such that it was aligned "in trail" with the elevator. Used 9V battery to retract the trim motor to the "full forward" position. Placed masking tape along the side of the trim motor pushrod slot. Marked on the tape the position of "full forward". Used the 9V battery to move the trim motor to the "full aft" position. Marked this position on the masking tape. Measured the distance between the two positions and divided this measurement by two. Marked this position on the masking tape as "Neutral". Used the 9V battery to move the trim motor to the "neutral" position. Trimmed the pushrod so that when installed with the motor in the "neutral" position the trim tab would be "in trail". With the push rod installed, moved the trim motor to "full forward" and checked the alignment of the trim tab. Then moved the trim motor to the "full aft" position and discovered that the pushrod was impacting the elevator at the aft end of the slot before reaching the "full aft" position. removed the push rod and used a round file to lengthen the slot until the push rod would reach the "full aft" position without impacting the elevator skin. Removed the trim motor and set aside to build the wiring harness. Cleaned out the inside of the elevator where the trim motor is installed with a vacuum. Cleaned the filed area of the elevator skin and sprayed the filed area with yellow zinc chromate primer to prevent corrosion. Fabricated rod-end bearing installation tool out of two pieces of PVC pipe and a PVC "T" connector. Started by cutting a slot in one end of the smaller pipe so that a rod end bearing would fit into it. Then inserted the smaller diameter pipe into the larger diameter pipe and attached both to the "T" fitting. Secured all pieces with screws. Used this tool to install the two rod end bearings in each elevator per the engineering drawing SWG 5, Detail D.
