[John G]

I am working on installing the Dynon A/P pitch servo in my RV-8 QB fuselage. As you can see in the attached image, there is interference between the head of the forward servo mount bolt, just behind the bell crank pivot bolt, and the rivets in the elevator bellcrank.

It seems like this would be a common problem, so I am hoping to hear how others have solved it. My plan is to change the two rivets that are interfering to countersunk heads, and to shift one washer from the right to the left of the bellcrank to move it over to the right by 1/16". These two changes should get me about 3/16" of clearance.

What have others done about this problem?

Thanks, John

 

[rvator51]

On mine, there are no washers under the head of the bolt so it does not interfere with the bellcrank. Also, both of my bolts have a hole drilled through the head and the bolts are secured with safety wire.

 

[boomer]

I used countersunk rivets all around, with the heads on the left side. Works fine.

-John

I am working on installing the Dynon A/P pitch servo in my RV-8 QB fuselage. As you can see in the attached image, there is interference between the head of the forward servo mount bolt, just behind the bell crank pivot bolt, and the rivets in the elevator bellcrank.

It seems like this would be a common problem, so I am hoping to hear how others have solved it. My plan is to change the two rivets that are interfering to countersunk heads, and to shift one washer from the right to the left of the bellcrank to move it over to the right by 1/16". These two changes should get me about 3/16" of clearance.

What have others done about this problem?

Thanks, John

 

[dwrichey]

Using a drilled head bolt with no washer(s) is a good solution. If that not enough security, one could also use an internal star type locking washer, their 1/32" thick. Trying to obtain a full 3/16" clearance seems a bit of overkill. I am more concerned with your use of pop rivets to hold the brackets down, wouldn't # 8 bolts be a whole lot stronger? This is an area you don't want anything moving around.