[RickWoodall]

Anyone know of a good site detailing the adjustments of the manual trim cable. Its routed, tail is final installed and just trying to adjust trim to spec'd travel. We have adjusted the cable several times, threaded it out/in, spun the clevis end in and out and still having trouble getting it just right. Cant seem to find good build site detail on how/if others have had trouble with the fine adjustments and what we might be doing goofy. Any suggestions welcome...

 

[Hawkeye7A]

Here's what I did

I posted a similar question some time ago and after melding all the responses, this is how I set mine, although on a -7A. You need a bit more up trim than down so I first determined how many turns were available on the knob; ~10 turns stop to stop. The proper ratio of pitch up (tab down) to pitch down (tab up) was 7:5. From the two stop points I kept adjusting until I had ~35mm tab down (pitch up) and ~25mm tab up (pitch down). This measurement was taken from the trailing edge of the left elevator to the trailing edge of the trim tab. As I was also told during my question and answer series, the amount of trim you will actually use during all flight regimens will not amount to more than 1-1/2 turns of the knob TOTAL! (If that much) This proved to be true. As with many other things during the build, the anxiety of anticipation is far worse than the actual task. Hope this helps.

 

[cwreeves]

Manual Trim

I measured the total travel of the cable between the knob and cable base (where it mounts to the plate) divided in half, moved the knob to match the 1/2 distance, set the trim tab to neutral and adjusted the clevis to match. Works just fine.
Charlie