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TruTrak Pitch Servo Mounting

Phil

Phil

Well Known Member
I'm getting ready to drop in my pitch servo at the elevator bell crank and trying to figure out where (or how) to locate the proper location for the attach hole.

This is the hole where the bar attaches to the bell crank arm.

http://www.trutrakflightsystems.com/documents/RV10pitch.pdf

What's the secret?

I know you have the threaded rod end bearing as adjustment, but what's the process to get it all adjusted and to reconcile any deviations in hole locate to the proper position on the servo?

I'm sure this is much simpler than I'm making it, but I'd like to know what I'm doing before doing it.

Thanks,
Phil

Also: I'm guessing I remove the locking nut that holds the wheel onto the servo so I can mount it through the bracket? Then reinstall after mounting it and safety wiring the bolts?
 
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Been awhile

Been a long time since I installed mine (NOV 07). I do remember removing the wheel. Attached is the pic to my installation. Not a lot to go by, but maybe it will help.

615354157474b5274ce10b.jpg


Eric
 
Thanks Eric... Now I know I have to remove the wheel at least. :)

Do you recall what the blue cross hairs were for? They seem to exist in your photo and the trutrak photos.
 
Eric,

There is a AD/SB or something:rolleyes: like that for the pitch servo to replace the screw with a self locking nut. The servo needs to go back to Trutrak to be modified if you haven't alreaady done so. The nut adds a bunch of confidence to the system. Mine took two weeks to turnaround including shipping time.
 
SB

Thanks for pointing that out. I was off playing GI Joe for awhile and I apparently missed that whole deal. Contacted Trutrak and as soon as I get the SN off the servos they will send the piece for the roll trim and give me the RMA to return my pitch servo for mod. Never thought to research that while I was looking up software upgrades I needed to catch up on.

Eric
 
Sorry about the pictures without dimensions. I think I have one floating around somewhere that I had intended to get on the website. :)

The hole is 2.5" up from pivot point and 0.25" aft. Those are rough dimensions, they don't have to be perfect. Anywhere in that region will work.
 
Phil,

They are for the mounting bolts, if you notice on Eric's picture he, as most of us I believe, used drilled head bolts and safety wired them. The TT method was to use locking or star washers.
 
Ahhhh. That makes sense. No way I'd trust the washer alone. I'm planning to safety wire them too, so I'll toss the washers in a bucket.
 
If the Trutrak tech will email me ([email protected]) I'd be happy to send them my dimensioned version of the image from the .pdf on their site. This question keeps coming up and apparently the search engine here is not adequate to locate past threads on the subject. It would be better if the info was in the installation .pdf anyway.
 
Why does my installation look so much different? :confused:
Note that this is an early picture before wire locking.
rv10_075.jpg
 
Jan,

Yours looks different because you don't have the "torque enhancer" version recommended for the RV-10. It replaces the arm with the wheel/bar arrangement.

Bob
 
I'm going to try and write a real RV-10 installation document for the servo, this way they can put it on the site.

I will share it as soon as I get it completed.

-------------

On the topic of the torque enhancer, I'm not sure how a standard servo would work. Perhaps Lucas can comment on that. The servo in the photo appears to be the standard servo used for the roll axis. I'm guessing you could add the torque enhancer to the standard servo if it's needed.

Also, looking at the photo, I see something else that we might want to kick around. The attach point is exactly on the center line of the bell crank. I believe (after a phone conversation with TruTrak support) that their suggestion for a slightly aft attach point prevents the bell crank from going over-center and getting into a position where the servo can't properly drive the elevator.

It may not be a real problem. But in the spirit of seeing something odd I feel compelled to point it out for discussion before it really does become a serious problem.

Phil
 
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Phil,
Thank you very much. I will make VERY sure about it not going over center. I also have the stops on the servo side to prevent that. As far as I remember I have checked it very carefully about a year ago when I have the tail feathers on.

Cannot remember, but at the time I have ordered and received the ADI-II and two servos. I did not know about this torque enhancer for the RV10.

From the pictures and the link I cannot see how the wheel "drives" the bar?

There is still time to change my setup if it is necessary. All advise will be welcome.
 
Jan,

I'll try and post a video of how the wheel works tonight. Basically the wheel drives a steel cable wrapped around the wheel to move the bar in and out.

Phil
 
Jan,

I didn't get a chance to shoot a video of it, but I snapped some photos on my way out the door this morning.

Basically the servo turns the wheel and the steel (wrapped around the wheel) drives the bar forward and back.

Here's the first photo of the bar, cable, and wheel.

IMAG0182.jpg



Since I haven't safety wired the bolts yet, I just sat it on the servo so you can get an idea on this next photo.

IMAG0183.jpg



Phil
 
Wunderbar! Thanks Phil!
I assume Trutrack have these part in stock and will try and order it.
One of my friends always says "Nothing is as it seems" :)
 
Which mounting bracket?

This thread shows two different mounting brackets...which one is the current model? Can either be used?

Here's a picture of mine...not finalized yet though. Will it work with the today's servos? I have not bought mine yet.

P.S. The nuts are there just to keep track of the bolts with the drilled head.



Thanks!

Jim
 
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