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Elevator trim servo not lining up.

O

OLDSAM

Well Known Member
When I mounted the elevator trim servo to the cover/support plate in the bottom of the left elevator in accordance with the dimensions given on the plan, the servo shaft is lined up with about the edge of the slot for the pushrod, rather than centered on it. Shouldn't be too difficult to fix, either redrill for the servo support angles, probably meaning a wait for the new plate from Van's, or leave it where it is and widen the slot when installing the pushrod later. I guess I am just a little surprised because this is the first thing in the empennage that has not lined up perfectly; even the elevator horns that have been ill fitting for some were spot on without having to mess with the spar bends at all.

Anybody else run across this? Am I expecting too much perfection without having to make any corrections to the plans?

(No, I did not measure for the support bracket from the wrong side of the plate, though that would be easy to do from the plan detail that looks up at the bottom of the skin instead of down from the top.)

Like DaX, a ramblin reck and a helluva engineer.
OldSam
 
Sam,

Were there dimensions on the plans? I think I just eyeballed mine until it looked like it lined up right. This took some time (at least an hour). I didn't space things out perfectly either, and ended up having to trim some material from the support plate that gets riveted to the inside of the elevator skin.

Do you have a picture? The fix is probably going to depend on what kind of person you are - if you're trying to build a show plane, you'll probably want to re-order parts and fix it. If you're trying to get the thing in the air, you'll probably make it work like it is.
 
I had the same problem. I just re-ordered the base plate and did it over adjusting the layout as needed for a good fit.
 
This is one place where the dimensions given in the plans are just plain wrong. I ordered a new plate and shifted the holes about an eighth of an inch. Fortunately, there have not been many such mistakes in the plans.
 
Thanks for the help, guys. Van's suggested that I drill new holes in the servo support angles rather than in the cover plate. I did that, but the new holes were too close to the old ones to suit me. I then added some new holes in both the plate and angles at a safer distance, but didn't like the way that looked either (12 rivets to support one small servo?). So I have decided to just order new support angles and cover plate (about 11 bucks or so total). Then I will locate the servo and supports to align the shaft with the slot, instead of just drilling per the dimensions. I think I will add some ProSeal and a VAF cap or t-shirt to help justify the freight.
 
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If you haven't done it yet

I mounted all of that last week. Just to make sure you don't make the same mistake I did. When you fit your trim tab, get all edges right and verify the trim tab horn is lined up with the servo on the elevator. I just ordered a new hinge to move my trim tab over about 1/8". Good Luck
 
mine lines up fine?!?

Hi,

I had bookmarked this thread to have a look when getting there... ...which means today. First thing I did was to cross out the measurement in the plans, but out of curiosity I marked them on my parts anyway. The surprising outcome: the servo shaft is dead on center of the cutout.
Just wondering why it sometimes fits and sometimes not. My servo is the T3-12A from rayallen, the part number of the brackets is EET-602B-L (or -R). Also there`s no statement of a recently revision on the plans.

By the way - since the servo attatchement plate is thicker (0.032) than the skin (0.020) the plate sticks out a bit. It's supposed to be that way, isn't it?

Mario
 
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