Elevator Alignment

I mounted my elevators to the horizontal stabilizer last night. With the counter balances clamped in the trail position, the trailing edges of the left and right elevator sides do not align. One side is about ?? higher than the other at the trailing edge. Has anyone had this problem? If so what was the fix?

I read another post that indicated that the elevators may be warped. However, I can not visually tell that there is any warping until I mount the elevators. I do not see how you can warp the elevators unless the pre punched holes are off. My trailing edges are straight.

Eulice Curington
RV-10 Empennage Serial # 40596

ecurington said:

I mounted my elevators to the horizontal stabilizer last night. With the counter balances clamped in the trail position, the trailing edges of the left and right elevator sides do not align. One side is about ½” higher than the other at the trailing edge. Has anyone had this problem? If so what was the fix?

I read another post that indicated that the elevators may be warped. However, I can not visually tell that there is any warping until I mount the elevators. I do not see how you can warp the elevators unless the pre punched holes are off. My trailing edges are straight.

Eulice Curington
RV-10 Empennage Serial # 40596

Click to expand...

Hi Eulice-

Trailing edges can be straight and have twist in them at the same time. It is also quite possible to have a twisted trailing edge with the pre-punched stuff. (One of my flaps has a 1/4" warp or twist to it--might have to rebuild if I can't live with the cosmetics.)

One way to figure out if this is true in your case is by running a piece of fish line from outboard corner trailing edge of one elevator to outboard corner trailing edge of the other elevator. If your trailing edges are warp free, you should be able to line them both up on the fish line.

When building, even withthe prepunched stuff, you MUST have a perfectly flat surface and MUST weigh everything down while drilling and riveting.

Good luck.

Are you comparing the front end of the elevators with the fiberglass tips on, or just the metal structure???

Just the metal structure.

Are you sure the horns are drilled at the pushrod connection, as straight as humanly possible? As per page 11-3, figure 3. If not that will certainly put them off. Ask me how I know.

Resolved

Checking the trailing edges with the fishing line told the story. The trailing edges were warped. I drilled the rivets out of the trailing edges and slipped a hacksaw blade in to cut one of the foam blocks to allow me to align the trailing edges with the fishing line. When I put it back together it all aligned and looked good.

Thanks for the help solving this one.

Eulilce

ecurington said:

Checking the trailing edges with the fishing line told the story. The trailing edges were warped. I drilled the rivets out of the trailing edges and slipped a hacksaw blade in to cut one of the foam blocks to allow me to align the trailing edges with the fishing line. When I put it back together it all aligned and looked good.

Thanks for the help solving this one.

Eulilce

Click to expand...

Good job, Eulice. Glad the suggestion worked out.

Out of curiosity, had you prosealed or epoxied your trailing edge before riveting? The reason I ask is that I have that trailing edge of the flap that I'd like to straighten out a little. Removing the rivets is no big deal, but I'm wondering if it will be tough to get that wedge out (or loosened) with the proseal in there.

Steve,

Yes I had pro sealed the foam block in the trailing edge. One elevator did not have that bad of twist and I was able to fix it without cutting into the foam block. On the other elevator I was not able to get the twist out without relieving the stress at the foam blocks. After drilling the rivets, I used a hacksaw blade and slipped in to cut the epoxy joint between the block and the skin. This allowed me to remove the twist. I then reapplied the proseal at the cut with a toung depressor and reriveted the trailing edge while keeping it strait along the fishing line.

It was easier to fix than I originally though after reading some of the posts with similar problems. Took me a couple of hours for both elevators.

Eulice