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Electric trim install

nohoflyer

Well Known Member
Patron
I?m installing the electric trim kit now before I close up the elevator. The elevator plans has drawings of the build but there is no mention of it in the instructions. Are guys just winging it? I?ve been on a few blogs for guidance but a step by step would be nice.
 
What I did in my RV-9

I just finished installing the electric trim in my RV-9. There was a little bit of "winging it", but basically I did the following:
*Checked the plans and drawings to ensure I installed the servo plates in the correct spot, and only riveted when I was sure it fitted properly.
*did lots of drilling and test fitting throughout

*Ensured the servo shaft and clevis didn't hit anything through full travel stroke (it didn't).
*Put snap bushing into the elevator spar hole
*held the trim tab in-trail with the elevator trailing edge
*Checked the length of the threaded rod between the servo & trim tab clevises, then cut it.
*wired up the switch, indicator, and servo (with a milwaukee 12v battery), drove the servo to the exact mid position THEN I cut the rod.
Finally I screwed and pinned everything together and tested again, checking that the servo electric cable didn't foul on the servo jackshaft. Re-checked for full range of movement without binding.

Lastly, can I say that I can't help it, I'm an Engineer. My wife knows it's a recognised condition.
 
Ya you have to wing it somewhat. The only thing that isn't obvious was I machine countersunk the two aft z-bracket rivets that are under the motor instead of dimpling (the motor is quite low to the plate here). You will also have to elongate the slot/opening for the rod. Mike B has a great build log here.
 
BTW, I found that Van's dimensions didn't work for my install. The lateral spacing of 1 3/8" from the edge pushed the servo too far off center. I found I needed to pull it in more to get a centered fit with the trim tab cut out and horn. Use the measurement as a guide and then adjust as needed. In my opinion...
 
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