Hi, I have been trying a lot of different ways of making pull pull system but they dont work well. What is the best way to do it?



Thanks,


Gabriel

Spiderwire or monofiliment fishing line is what most of us are using for the cables. Then just use standard control horns and servo arms, or make your own from carbon fiber, coffee can lids, old credit cards, etc.

Put the control horn on the control surface as close to the hinge as possible, and make sure its locked in there good and solid with glue. Then tie on your cables.

The cables dont need to be super super tight. If you tie them too tight, they fight against the hinge, and will pull the hingetape up. Just tie them tight enough so that they are not floppy.

If your pullpulling the rudder from inside a enclosed fuselage, cross the wires over inside the fuselage to keep them from rubbing the fuselage walls or binding.

Originally Posted by Bryan Davison

If your pullpulling the rudder from inside a enclosed fuselage, cross the wires over inside the fuselage to keep them from rubbing the fuselage walls or binding.

Why didn't I think of that?! Thanks Bryan!

From a geometry point of view, the servo arm length and the control horn length should be the same. If the control horn is too long compared to the servo arm you will have wires that loosen in use, leading to slopping controls. Slightly longer servo arms than control horns is OK as it will add tension to the system in use.

Mike

Thanks for the tips!