Question on the FT Cub - my 1st build!

[dave rose]

Hi all.
This is my first build!! The FT Simple Cub. My question is on the push rods. There is a straw-like sheath (didn’t see it until after I built) and zip ties. My question is when I run the rudder, one direction the push rod just bends in the plane and not swing the rudder. So I think I have to have the pushrod in the ‘straw’ but not sure. What could I do in 3-channel mode to make sure the rudder swings both directions?

 

[PsyBorg]

I believe the straws are pass thrus the control wires use so they dont cut holes in the foam. the zip ties can be used for a number of things. Supporting the control rods is one of them. Basically make a small loop with the zip tie. Cut off the excess about half an inch (13mm for non imperials) on an angle run the control wire thru the hole then poke the shaper pointy end into the fuselage and hot glue in place where the control wire aligns straight.

You can also if you have long control rod distances heat shrink a bbq skewer along the length of the rod to prevent flexing.

If your servos were properly centered when you installed them then you should easily be able to move the rudder both ways. if not just remove the servo horn, power on radio and make sure channel and trims are centered then reinstall the control horn where the rudder is as straight as can be made. then go back and use sub trims to set a permanent perfectly straight start point.

 

[kilroy07]

Hi all. <snip>

Hi there, and welcome to the forums!!

You can also check out this video at 21:45

You can see how they use zip ties to help manage the pushrod flex on one of the wings.
Works great.

If it seems to flex a lot, look for a reason (maybe too much glue on the joint) that might be binding everything and making the servo work so hard to push the rudder in that direction. Also check and see if the rod spins freely on the horn side this can cause a lot of flex in the rod as well.

Hope some of this helped.

 

[Matthewdupreez]

In quite a few of the planes cub included. You must run the pushrods through the straws .. to prevent flexing
@dave rose