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Elevator misalignment

D

dpz

Member
Hey All

Just put on my elevators as per instructions ( horns are flush with stabs skins) drilled all holes and noticed my right trailing edge is about 1/4 inch lower than my left when looking down the edge. Been searching the forums and see that this does occur from time to time . Im going to get a laser and check for alignment. Ran string down from one elevator corner to other corner and i have no twist. With string taught makes it appear to be almost gone ( could be illusion). How many of you have seen this and what was your fix. I was thinking to having the drill hole welded and re-drilling with trailing edge straight by splitting the difference on the horns ( left slightly up 1/16" right slightly down 1/16". let me know of other any other solutions and if anyone had the same problem.

Thanks Much
 
Welding rod

If you decide to weld the hole or holes, the welding Vans suggested to my buddy was tig weld with rod ER70S-2. Aircraft Spruce sells this rod.
 
FLY6 said:
If you decide to weld the hole or holes, the welding Vans suggested to my buddy was tig weld with rod ER70S-2. Aircraft Spruce sells this rod.
Click to expand...

ER70S-2 is a common filler rod for carbon steel. Almost everybody sells this rod to include some Lowes, HD's, and Harbor Freight not to mention your local welding supply shop.
 
At the risk of stirring up a hornet's nest, my suggestion would be to fly it as is.

Yep, there'll be a tiny bit more drag, and perhaps a very slight roll, but you may not even notice.

Popcorn popped, expecting incoming.............!
 
This happened to me on my 14A. I called Vans tech and they said build on and stated " you can have both elevator horns flush with the stab or the elevator trailing edge flush, but not both". Not worth messing with.

More common than you think. You dont notice on completed aircraft because the rudder obscures the view of both trailing edge elevators for comparison.

Jim
 
Vans advice

I talked with Vans support today and his told me his rv-7 elevators were out because of a twist and it flew fine. I just shimmed the two horns to make the T/E straight and it is about .075 up on the left horn and .075 down on the right horn to correct it.That would mean getting one drilled hole welded closed and re-drilling with the split in the horns. Everyone is leaning towards leaving it alone and it wont really matter much. So I guess I should continue building it , fly her and if it is an issue I could take off the right elevator weld the hole and re-drill with the split in the horns. Sounds like this is pretty common out there!

Any more suggestions are appreciated.
Thanks
 
Any more advice

I decided to build on and worry about it later if it is an issue.

any other suggestions apreciated
 
pilotkms said:
I welded mine and redrilled so they match. I sleep much better at nite.
Click to expand...
Isn't the welding and re-drilling needed when the horns don't match up with the HS?
The issue here, as I understand it, the horns do match up which means it was drilled correctly but the trailing edge is in misalignment.
 
Horns match

Yes my Horns do match but my right T/E is 1/4 inch lower than left T/E. When you welded the hole closed was it any harder to drill thru? How much were your trailing edges mismatched and now how much are you horns mismatched now? Can you noticed the horn mismatch? How does it Fly? Sorry for all the question but I was leaning towards welding and matching the trailing edges, just wanted to hear your experience.

Thanks
 
dpz said:
Yes my Horns do match but my right T/E is 1/4 inch lower than left T/E. When you welded the hole closed was it any harder to drill thru? How much were your trailing edges mismatched and now how much are you horns mismatched now? Can you noticed the horn mismatch? How does it Fly? Sorry for all the question but I was leaning towards welding and matching the trailing edges, just wanted to hear your experience.

Thanks
Click to expand...

Does the entire TE mismatching or you are measuring from each corner of each elevator?
Can you measure the angle of each elevator (using a digital level) when the horns are locked in place to the HS and see how they differ. It would be good to do this measurement at different location on each elevator to see if there is any discrepancies.
 
Horns matched

Yes my Horns do match but my right T/E is 1/4 inch lower than left T/E. When you welded the hole closed was it any harder to drill thru? How much were your trailing edges mismatched and now how much are you horns mismatched now? Can you noticed the horn mismatch? How does it Fly? Sorry for all the question but I was leaning towards welding and matching the trailing edges, just wanted to hear your experience.

Thanks
 
Elevator

When I look down the trailing edge is when I noticed it, after I drilled the control Tube hole. I then taped fish line and pulled it very taught against the left T/E and it was about 1/4 inch above the right T/E. I also tried to shoot a laser down the T/E but depending on the reflection and width of beam it was harder to determine how much it was low. If you stand behind it and look it also appears lower. So my best guess is about 1/4 inch low.

Do you know another way to measure it?

Maybe on a flat floor and make the aft corners of the stabilizer the same height from the floor I would be able to measure off the floor of the trailing edges??

Thanks
 
Elevator horn misalignment

First, I am a legacy builder. I have built a Three, Four and a Six. My experience with a "pre-punched" assemblies is limited to my recently build of an RV-14 horizontal stab and elevators. After the initial construction was complete I mated the elevators to the stab and found the elevator horns to be well out of alignment. So to quickly resolve the problem I cut through the round tubing on the "offending" elevator horn off half way between the elevator horn and inboard rib of the elevator. I then placed a two inch long piece of tight fitting 4130 tubing (sleeve) inside the elevator tubing, rosette welded in place, mounted and "re-clocked" the elevator horn over the remaining end of the 4130 insert and rosette welded it in place. Finally, a butt weld was made over the entire mated joint. I chose this path because it was a quick fix, didn't involve disassembling the elevators, and it got my project done faster than any other avenue I knew. The fix is HFS!

Chuck Brietigam
RV-6XXL
 

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Horns match

When I wrote about horns I meant the elevator counterbalance arms that get duck taped to the horizontal Stab, when they are in the elevator trail position
thats when i see and measure the right elevator T/E 1/4 inch low.
Can anyone think of a good way to measure the difference between the 2 elevators T/E?

Thanks
 
CT Brietigam said:
First, I am a legacy builder. I have built a Three, Four and a Six. My experience with a "pre-punched" assemblies is limited to my recently build of an RV-14 horizontal stab and elevators. After the initial construction was complete I mated the elevators to the stab and found the elevator horns to be well out of alignment. So to quickly resolve the problem I cut through the round tubing on the "offending" elevator horn off half way between the elevator horn and inboard rib of the elevator. I then placed a two inch long piece of tight fitting 4130 tubing (sleeve) inside the elevator tubing, rosette welded in place, mounted and "re-clocked" the elevator horn over the remaining end of the 4130 insert and rosette welded it in place. Finally, a butt weld was made over the entire mated joint. I chose this path because it was a quick fix, didn't involve disassembling the elevators, and it got my project done faster than any other avenue I knew. The fix is HFS!

Chuck Brietigam
RV-6XXL
Click to expand...

Exactly like mine. Vans could do a better job in matching a set before shipping.

Michel
 
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