Rudder Cable Rigging (6 hr)

Finally, we have some control cables rigged. I can’t remember how long ago it was that I thought this was going to get done but it is finally done!

Allen was able to join me for most of the day and he had worked out a new way to set the rudder deflection angle: take one plum bob, a printed protractor from the internet and some sharpies.

We set the paper protractor on the pivot point, extended the 23 degree lines on the floor and then with the plum bob on the tip of the rudder we could move it left and right until the weight was on the angle line. Place the rudder stop against the rudder and trace around it to mark the position. It took quite a while to get the stop the right way around, it is not obvious from the plans (well, wasn’t to me).

While in Japan, the new torque tube bearing had arrived and for a while we were stumped because the holes did not match the earlier bearing. It seems that Zenith have added a couple of extra holes into the fairlead.

I filed the inner hole a little so that it fit better on the tube and then we positioned it in place so we could make sure that it held everything in the right place, clamped it and then removed for drilling. In retrospect we probably should have just drilled new bolt holes but instead we went to some effort to reuse the existing ones – not easy with then being inside a tight space.

After reassembling the torque tube we could attach the rudder cables. It took a while for us to come up with a way to work out where the pedals should be in relation to each other at different deflections, keeping in mind that the nosewheel is also involved. After some adjustments and readjustments we swaged the connectors onto the ends and the cables were set.

Some messing about with the turnbuckles at the rudder end got the cables nice and tight.

The plans call for 30lb plus/minus 5 so we look good, and I suspect the cables will slack a bit over time.

I wish I could have sat in the plane and taken some video of me pushing the pedals and moving the rudder but the nosewheel is impossibly stiff right now, only way to move it is a crowbar in the fork. I’m squishing silicon lubricant into the nose block every visit, hoping that will do the trick.

Allen left and I finished the day with some ‘tedious’ tasks…. riveting the rudder stops on

…. the torque tube bearing….

At some point the temperature in the hangar made it over 100F

The next item will be the elevator control cables so I set the elevator in neutral position against the stabiliser.

I reassembled the bellcrank on the torque tube inside the fuselage and started to pull the cables from the tail through until they were a little tight, secured them with clamps. They are still a way from being tight enough but next hangar trip it should be fairly quick to finish.

The cable assembly on the bellcrank could probably do with being a bit shorter on the top, the join is going to be a bit further back in the fuselage that will make it harder. Also, it was difficult to get access because right now the fuselage is sat back on the tail so the access hole is lower to the ground. Hopefully these things will be easy to work around next time in the hangar.