Fuselage control run choice

[Nigel R]

Those thin snakes are also fairly good guides for closed loop wires, in this instance only need glue at one end, or the mismatched expansion problem will mean changing tension of the wires.

 

Not much cop at being control runs themselves, though.

[Martin McIntosh]

Snakes these days are old hat except if you want an easy option such as Sullivan when you can simply screw a threaded rod into each end and are not too fussy about control slop. I used similar for many years with what I called macaroni tube and steel Bowden cable but the trick to avoid slop was to get them perfectly straight to start with. This was done by inserting piano wire into a piece soaked in boiling water. The odd crimp with some wire cutters here and there helped too. If you think about it, a cable inside a curved tube, assuming that it is free enough to move, will need to take up any side play before it moves the control surface.

I now use closed loop on rudder and if possible 2 or 3 mm i/d carbon tube with a threaded rod well and truly JB welded inside for elevator. Hard balsa bound to wire with thread is also very good.

[gangster]

A friend of mine filled snakes to a model that had already been covered by drilling through an appropriate size piece of balsa which he slid down the snake. The wood was primed with white glue and pushed against the structure