Rudder cable tension for Tri gear

[Mike53]

Any Onex tri-gear builders experiencing stiffness or generally not easy movement of the rudder pedals?
At first I thought in might be a binding in the rudder hinge but when I disconnect it from the cables it's very easy to move.
When I work the rudder pedals they require some effort to move and I'm getting oil canning at the fire wall where the cables exit the cockpit and change direction.
It occurs to me that the turning moment on the nose wheel shaft is high up and the mechanical advantage of such an arrangement is not ideal as say if the turning moment happened at the middle of the shaft.
Any how just wondering if any one else has thought this a problem.
Thanks.
Mike

[Onex107]

Mine are installed as per the drawings. I did cut my nose wheel post off. With the weight on the nose wheel, slide the steering arm down as far as it will go and redrill the bolt hole. That lowers the arm a couple of inches. Also, I used the springs and short turnbuckles at the post to adjust the tensiion. The springs give a little delay in the wheel turning but they do not feel stiff. My battery box is mounted above the nose wheel shaft and I shortened it to increase the spring tension and keep it from hitting the bottom of the battery box. I don't know how to add pictures to this post or I would show you my set up. Email me at flyvfr@comcast.net and I'll send them.

[thomasjones42]

Still building and I also find the nose gear movement to be extremely stiff and while I mounted it over a year ago and exercise it frequently, I don't find it has loosened up very much. I worry a bit about how much rudder smoothness will be possible, given how stiff the nose gear makes rudder pedal movement. No solutions.

Tom Jones
ONEX Plans #133

[Mike53]

Still building and I also find the nose gear movement to be extremely stiff and while I mounted it over a year ago and exercise it frequently, I don't find it has loosened up very much. I worry a bit about how much rudder smoothness will be possible, given how stiff the nose gear makes rudder pedal movement. No solutions.

Tom Jones
ONEX Plans #133

Hi Tom.
Morrie's Onex107 above said that when he hung the engine the spring compressed and of course the nose wheel strut extended out the top a couple inches so he redrilled the hole on the pivot arm thereby giving a little more mechanical advantage to the turning motion.I haven't tried it yet but anything that would lower the turning moment down the strut should make it better.The ideal would be if it was centred on the strut but that is impossible.
I will be giving it a try next week and will let you know if it helped.
Mike

[Onex107]

When the wheel is rolling, it is not so stiff and turns very nicely. The springs let you make rudder corrections. It would turn quicker with individual brakes, but I find that braking during the turn, both wheels, which you have to do depending on your idle rpm, makes the turn faster. During rollout you have to dance on the pedals a little bit to stay straight. I think I need to re-tension my cables. That's why that small turnbuckle is so important.

[thomasjones42]

Morrie,
Where did you find the turnbuckles?

[merle reppert]

The wheel strut flexes quite a bit and will BIND in the brass bushings if they are to tight
More clearance will let it turn easier---

Merle Reppert

[Mike53]

The wheel strut flexes quite a bit and will BIND in the brass bushings if they are to tight
More clearance will let it turn easier---

Merle Reppert

Interesting .Now I wonder if I have too much tension on the cables.Merle did you drill for the bolt at the top of the strut?
Mike

[merle reppert]

Not sure what you mean about the bolt at the top---There is a bolt through the strut and the
steering arm---If you over tighten this bolt it will also cause friction on the strut --
With the closed loop design of the rudder cables ---From nose strut to the rudder hinge
and back to the nose strut --There is a lot of tension and drag---I have two Onex's flying ( Both
Trikes )and if I change power setting the BALL will move off center ---The rudder does not self center the Ball due to friction in the cable system --
Merle

[thomasjones42]

Had my first Tech Counselor visit two days ago. I had the Onex on stands so that the nose wheel was free of the floor. The Counselor expressed a concern that I have been harboring for sometime that the stiffness in operating the rudder pedals is unsat. A couple weeks ago I disassembled the nose gear and polished the stut, bushings and washers but couldn't see much improvement when I put it back together. Aside from negating the ability to make small movements ("dance") on the rudder pedals given their stiffness, the Counselor also expressed concern that the nose gear would be too stiff to seek a centered position in flight and could adversely affect yaw. In order to isolate where the drag originates we disconnected the nose gear steering arm from the rudder cables and as expected the rudder pedals operate quite easily when not connected to the nose gear. Later I removed the spring from the strut and not surprisingly, the nose gear/strut turns quite easily without the resistance from the spring compression.

After thinking about this overnight I'm wondering what purpose is served by the spring being compressed at all when there is no weight on the nose. It seems to me that it would be desirable to have the nose gear/rudders as free wheeling as possible in flight. I believe if I shortened the spring by a half inch or so, I could relieve the pressure/compression when there is no weight on the nose wheel, but still have the spring come immediately into play as soon as there is weight on the nose. Does anyone see a downside to doing this?

Tom Jones
ONEX #133
Trigear
Aerovee Turbo on order