jeffmoreau

jeffmoreau

Well Known Member
I am having an issue with my Trutrak roll servo hitting one of the braces on the underside of my front floor/footwell.
Has anyone ran into this? I installed the servo according to the drawing supplied with the unit. I am most concerned as I aware of how important to have the controls free and correct.
Any photos or advice as to how you solved this problem. I know that this floor must flex as you sit on the front seat.
I am afraid that even if I cut some of the floor stiffener away that the floor may still flex and touch the control arm of the servo and then bind the controls.
Please help me.
 
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Yes

I'll see if I can find the pictures. I had to move the servo back some to get clearance. I also bent the arm inward (toward the servo) approx. 10 degrees.

It took a little playing around, but I got it to work. No problems with 400+ hours.
 
Model Alert!

Looks like Jeff is building an -8A, and Darwin, yours is a 7 - right? Having both a -6 and an -8 in our hangar, I can tell you that two installations are worlds apart!

Here's a picture from my pile of construction photos - both the trim and autopilot servos are mounted per their respective drawings.
P3030033.JPG


Paul
 
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Jeff:

I had the exact problem on my -8. I couldn't believe it when I went to install the floor panel and discovered the interference. I checked the instructions and drawings and of course there is no indication of any such problem. Makes me suspect TT has never actually installed this in an -8 themselves.

At any rate, I cut the floor stiffener down as close as I could to the bend in the flange and far enough inboard to clear any motion by the servo arm. I've been flying with it for almost two years and have not noticed any binding or other problems. You won't depress the floor that much, after all there is a stiffener in place (though a little less stiff than before).

Sorry I don't have photos, but 5 minutes with Dremel and a file and you'll be good to go.

Chris
 
I just drilled off the angle and turned it around. It now clears the servo arm by about a half inch. No photo of the floor but here's the servo mounted.

roll1s.jpg


Good luck

Paul Danclovic
Jamestown NC
RV-8A N181SB
 
I'm having the same problem

Which of the three holes in the servo arm did you all mount the pushrod to? I have cut some of my floor stiffener away, but I guess I will have to keep cutting since I'm still getting some interference.
 
Ironflight said:
Looks like Jeff is building an -8A, and Darwin, yours is a 7 - right? Having both a -6 and an -8 in our hangar, I can tell you that two installations are worlds apart!

Here's a picture from my pile of construction photos - both the trim and autopilot servos are mounted per their respective drawings.
P3030033.JPG


Paul
Click to expand...


Paul,
Thanks for the reply. Did you have any issues? Mine is in the exact same place.
 
Good catch

Good catch Paul. Disregard my comments!! I guess I had just woke up from a nap.
 
Grind stiffener

I recall having to grind some clearance on the stiffener also.

Couldn't find a photo any better then Paul's. But my installation was just like his.

Ted
 
I had the same problem -- just to show this is pretty common. Would be nice if the dimensions were a little different or even a bit of a warning of the possibility in the instructions so one can avoid it.

The large diameter washer called for attaching the servo arm was swapped out for a small one. It was actually this washer that was hitting the stiffener.

Cut down the stiffener as much as I could.

For extra measure am using the second hole on the servo arm. I don't think it will make a difference. The servo is strong enough to make it move with a little less radius.

Consider it fixed and moved on.
 
Washer

The large diameter washer that is intended to hold the arm in position in case of rod end bearing failure was hitting on mine also.
Where did you locate the smaller diameter washer?
 
Moving to the second hole

Tom,

Just a heads up. If you move to the second hole down, check to make sure to don't come close to an over-center condition when rolling left. You probably checked this already, but just in case you missed it.

Chris
 
Same issues as everyone else. I drilled the stiffener off and then repositioned it. Also used a smaller diameter capture washer, and you must use the outermost hole, otherwise you will come very close to overcenter!
I have done both the Tru Trak and Dynon using the Tru trak mounts.
For the capture washer I used an extra one that comes with the rod end bearings for engine controls. These are smaller in diamter than an AN970-3.
Good luck!
 
Methinks that is the capture washer is the problem, you could grind a flat on it------would allow clearance, and still provide a safety for the ball joint.
 
Mike,
The stiffener is smack dab right over the servo arm/rod end assembly, so it really needs to be repositioned. Reversing it may work, but I chose to move it slightly to gain assured clearance.( The stiffener, that is!)
 
Servo on right solves the problems

I have taken a different approach on my 8. Fearful of floor interference and not liking the proximity of the signal connector and aileron push rod, I moved the servo to the starboard side which puts the linkage under the seat ramp and reorients the connector away from the push rod.
 
Ironflight said:
I don't recall having any issues, but that was three or four years ago, and some details might have been pushed out of RAM....;)
Click to expand...

Man, ain't THAT the truth! Combine being old with taking a long time to build and that becomes a very common occurrance. You have any idea how many times somebody will ask a good question here and I'll say to myself, "Yeah, I had the same problem ... now, how did I fix it?" No clue. :rolleyes:

This gettin' old isn't for kids ...
 
If your wings are not installed, why not just use the RV-7 roll servo mount in the -8? It puts the servo out in the right wing panel, which is what Dynon did for their installation in both the -7 and the -8. I am removing a Dynon AP from my -8, and installing a TT. The roll servo will go in the mount the Dynon servo is vacating. Lucas at TT says this will work just fine.

It might be a bit of a challenge if your wings are on since you'd be doing this laying on your back, but if they're not yet installed, turn the wing upside down and work from above for an easy installation.
 
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