Pull Pull with Tail servos
 

I modified and therefore mounted tail servos on my Sukhoi, and still have to install the pull pull cable for my rudder, but would hate to just lay the wires next to the servos and create a friction and/or tension against the servos there. What would be the best solution to avoid this ? Would laying the pull pull wires in nyrod do it ? Also, have you tried to run a long nyrod from almost servo arm to outlet of fuse ? Any input will be greatly appreciated.
Thanks

Pull Pull with Tail servos
 

Stuka
I seen a pattern plane set up with ny-rod outers from the sevo bay to the rear exit. The pull pull wires running through the outers. It seemed to be a slick setup and worked like a charm.

DEG

Double flex rods.....
 

Just something to think about....here's a set-up I'm using on a big 78" pattern plane.

Sullivan #585 semi-flexable, premium carbon fiber reinforced inner rod, with all 4-40 hardware.

I'm using it for the elevators ( seperate ) with one servo on each rod.....both pulling for up. Homemade hardwood "bullets" serve as guides.

Rudder set-up.....
 

Just something else to fodder the brain....

Here's how I did the rudder on the same plane....I'm not a fan of those tiny cables...
This angle is funny....the guides are actually in the middle of the connectors.

Over-all view....
 

.....rods cross over in fuse.

servo detail....
 

.......just something to generate your own ideas.
Part of the fun is doing it "any way you want".

Rigid rod pull-pull
 

Doesn't the way you've set up your rudder pull-pull with rods present the problem that the control horns must be perfectly positioned to avoid any positive or negative Ackerman? If they were off even slightly, wouldn't it cause the servo to bind? Please explain.

Yes, I suppose it could.....
 

....cause binding through the guide block, and resistance to the servo. The alighnment doesn't have to be perfect, but it has to be close, and the three widths have to be the same. A drop of pure silicon lube in each guide-block prevents binding, and wont attract much dust.
The control horns are moved rearward from the hinge line...It is a distinctly asymmetrical system. This is also positive Ackerman; moving the holes in the control horns forward would create negative Ackerman, and this would cause problems.


Remember to mount the antenna up high on the tail....away from cables or rods.

skyman....this is what takes place.....
 

.....with positive Ackerman. Notice the difference in deflection ?
It's only .004"....negligable..not a problem. There's enough play in the components, and flex in the servo arm, that the tiny bit of differential isn't noticed by the servo itself.