The idler plate for direct rudder drive, with spring drive to the tailwheel is
done --finally. The OOPS was recovered by placing bolts in cups just forward
of and outboard from the position of the holes for the cable in the original
tailwheel drive arm. The resulting pedal drive geometry for the idler plate
is now nearly a copy of the geometry from the original tailwheel arm; the
difference is that bolts are used to connect to the pedal cables rather than
holes with cable eyes. As with the rudder drive bolt, cups were formed by
drilling a 0.65 inch hole in the idler plate, then welding a piece of steel
over it and drilling a 1/4 inch hole in the center of each cup for the bolt.
Thus, the bottom of the idler plate remains flat so it can slide on the
tailwheel arm without interference from the bolt heads. The eyebolts on the
bottom of the idler plate are secured by sticky nuts and are cut off with 1
1/2 threads protruding so the cables can pass over them without interference.
Overall, it now functions as envisioned, although the path to completion was
not as smooth as I had hoped. Also, the parts count increased due to the
addition of the bolts, nuts, and washers for the cable terminations -- the
parts count is rather embarrassing when compared to Europa's elegant design
for the outriggers.
Duncan's suggestion of an arrangement with a single captive spring in
compression (as used in bunches for automobile clutches) seems excellent and
would reduce the parts count considerably. If I were to start over from
scratch this would be a likely approach.
But, the present design seems to function so it's onward and (eventually)
upward.
Regards, John A044 Newtown, CT
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