[bill price]

I am in the middle of an annual on my RV-4 and I noticed play between the left and right elevators. There is 1/4" play up and down in 1 elevator if I hold the other elevator stationary. The play is because the bolt going through the 2 elevator horns has a little play in it. If I tighten up the bolt will it remove this play or just sieze up the push rod to horn joint? Anyone know what is acceptable or what to do about it?

 

[Steve Sampson]

Bill, From the way you describe it, my suggestion would be rather than to just tighten the bolt up, first insert extra washer(s) alongside the pushrod bearing, between the two horns, so it is 'full'. It is a bit of a fiddle. You might need some thin washers to get it just right. Then tighten the bolt up. Remember to invest in a new Nylock. It is an important bolt! This way nothing will be stressed.

The centre of the bearing will be gripped tightly. It should not move with respect to the bolt. The rest of the bearing rotates around the central part, and should not touch the horns.

If you just tighten the bolt up you will stress the horns and their attachement to the structure.

Hope that helps.

 

[brianwallis]

gasp....

1. Remove the hardware.. it may be something deeper...
2. inspect everything very carefully
3. re-install.... and depending on the finding... we go from there...
Best of luck
Best
Brian Wallis
404-405-1315

 

[Mike S]

1. Remove the hardware.. it may be something deeper...
2. inspect everything very carefully
3. re-install.... and depending on the finding... we go from there...
Best of luck
Best
Brian Wallis
404-405-1315

What he said!!!

 

[rvbuilder2002]

1. Remove the hardware.. it may be something deeper...
2. inspect everything very carefully
3. re-install.... and depending on the finding... we go from there...
Best of luck
Best
Brian Wallis
404-405-1315

What he said!!!

What they said.

Inspection, means Inspection.

If you find something not right, disassemble to the degree required to find out exactly what is going on, "then" make a determination how to repair/rectify it.

 

[Tom Martin]

This is an area of airplane that I never cared for. The gap between the elevator horns is larger than the width of the bearing. This gap is supposed to be filled with washers. Typically in the RVs and rockets that I have been involved with that gap is close to 1/4". I take two pieces of flat aluminium,
1" wide, app. 2" long and 1/8" thick, and rivet them to the lower ends of the elevator horns. This substantually increases the thickness of each elevator horn at that critical point, and eliminates the need for washers. The bolt now has much more support and is less likely to get loose with time. An added benefit is that in this location washers are quite hard to put in place.
The thickness of the metal used in this location may vary from 1/8" depending on the installation but the theory is the same.

 

[Mike S]

I take two pieces of flat aluminium, 1" wide, app. 2" long and 1/8" thick, and rivet them to the lower ends of the elevator horns. This substantually increases the thickness of each elevator horn at that critical point, and eliminates the need for washers.

Sounds like a great fix---------only one question, to rivet the piece on, you have to drill a couple holes in a part that is already pretty minimum in size----makes me wonder if the rivet holes have a negative effect on the strength of the horn???

Any engineer types out there who can opinionate on this?

 

[Tom Martin]

Mike
The horns are 4130 and there are no edge distance issues, if any thing the part will be stronger rather than weaker. I am not sure what the elevator horns on a RV10 look like and my suggestion may not work there.

 

[Mike S]

Tom, thanks for the reply.

I like the idea of increasing the thickness of the part, just didnt know if the cure was worse than the original problem.

Bottom line here, is a failure on this one bolt will ruin your life, so it better be done right.

The actual setup needs to be locked together with the only rotation going on where it is designed to, inside the rod end.

Exactly like Steve said in the second post.

Fly safe.