Bend control rods?

[SWeidemann]

In the process of inspection and discovery of components on my third hand Kitfox I found a control rod touching a airframe tube during it's travel. I see no obvious adjustment to remedy however I did think of removing the rod and putting a slight bend in the tube. The tube in question is one of the front pushrods that activated the elevator. In the last part of it's travel it is hitting a V shaped weldment that holds the center seat belt brackets.

Any advice?

Thanks much,

Skot

[Esser]

Skot,

One of those pushrods has a bend in it. Make sure that it is orientated correctly. You might have to rotate it to get it to lift off the tubing. Let me know how you make out and if you need more clarification I can try to get a picture.

[SWeidemann]

Esser,

I know one rod (under the pilot seat) has an abvious bend in it and I am aware of that one. The (slightly touching) rod i'm talking about is in the center of the plane and runs down the fuselage to actuate the elevator. Are we talking about the same one?

Thanks much,

Skot

[Esser]

Hi Skot,

No I was talking about the bent one up front. Someone else may chime in but I think it would be safe to bend it in my opinion. Better to have a bent pushrod than one that interferes. Maybe take it off and roll it on something flat and see if there is a bend in it now which is causing it to hit.

[SWeidemann]

I think a removal and a slight bend would work as long as it is a gentle bend. I remember the first time I saw that obvious bend on a pushrod under the pilot seat I was so startled that it took me awhile to recover and realize it was "on purpose".

As an aside comment, I think this classic design airplane is very well engineered by some clever people who thought up all those control actuators, airframe build techniques and still made a relatively simple and efficient airplane. I'm also glad there is a large group of Kitfox owners/builders/fliers to talk to. Also, thanks to Deb & John for being in business to support all of us.

Skot

[Dutch]

Skot

areyou talking about the long control rod that runs down the center of the fuselage & connects to the elevator horn ? There should be no reason for that to have any kind of a bend in it. It should be connected to the bellcrank just to the rear of the seat. The bent rod under the seat connects to the bellcrank as well.

Dutch

[SWeidemann]

Dutch,

Not the very long reach rod, but the one attached to it (starting at the horn at center of the dual stick bar).

Skot

[JohnB]

Skot,
I had the same thing happen on my Super Sport project. The front elevator pushrod would contact the V shaped weldment with the stick full aft. On mine I was able to shorten the front pushrod by turning in the ball ends enough to prevent contact. Then I lengthened the aft pushrods to attain the same neutral position and elevator travel.

[SWeidemann]

I took a few shots that hopefully will point out the points of contact.

Skot

[PapuaPilot]

Hey, the pictures help!

I would try doing what JohnB suggested. If that doesn't work then a slight bend might would be an option. You would want to bend it right at the spot where it rubbed.

[jtpitkin06]

Don't bend anything, yet. Do more looking to find the fault. If you have rubbing, something is out of position.

Look at the following areas.

Elevator stops on control stick gimbal not adjusted properly (under right seat floorboard)
Bellcrank installed backwards..
Pushrod not adjusted properly
Rod ends not threaded in far enough.

Let us know what you find.

John P