Chapter 20 - Rudders

The rudders on SN413-689 are exactly per plans.  


The only modifications that were made were to the hardware for the rudder cable.  The plans thimble and Nico-press makes it very difficult to remove the cable from the rudder horn if required.  Additionally there are reports of the wind banging the rudders around and the cable getting flipped over, hanging the rudder up in a nearly full deflected position.  I'd hate to not catch that on a pre-flight.
After Michael had installed the rudder cables, they both became damaged in the finishing process.  I tore them out completely, and started over.  I ordered twNAS 1435-K2 fittings with the ends pressed on to 50' of rudder cable from Aircraft Spruce.  There is a hole-mismatch between the rudder horn and the NAS 1435-K2, so I machined a bronze bushing to take up the difference and give the rudder horn a nice bearing surface.

At the wing root there were reports of the aluminum fitting per plans having the holes get elongated.  I solved this by using two clevis pins and two link plates from a motorcycle chain.  The link holes had to be reamed to 0.1876" but they work well after that.  One safety pin retains both clevis pins.  Heat-shrink tube over the free end of the cable in the Nico-press keeps the ends from biting you when you reach in there,

The final bit was that the chain-link modification left me without any cable adjustment.  To remedy this I added two turnbuckles at the rudder pedals.  

This required modification of a rod end bearing to work with the turnbuckle, but that was just a slot cut for the turnbuckle retention pin.  It looks and works great.

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