Started the build of the rudder today. First job was to weld the upper bush to the fin main spar. This is a 7/8" piece of tubing that provides a good rotating fit on the rudder's 3/4" front tube. The plans call for spacing the rudder off the fin slightly to allow for the thickness of the covering so I welded the 7/8" bush into a piece of 1" tube using 3 rosette welds to provide the clearance. The 1" tube was then welded to the fin spar.Next job was to drill the lower section of the fin spar for the 5/16" tube that passes through it to provide the stiffener for the lower rudder bearing bolt. The fin spar was indented slightly round the holes to allow the weld to lie flush with the spar surface when the cross tube was welded.
The lower rudder pivot was then fabricated. The pivot arms were bolted in position and the bush positioned between them with a small section of 1" tube inserted behind it to match the spacing of the top pivot. The arms were then tack welded onto the bush. The outside of the joint between the arms and the bush were then final welded and the interior brazed to provide additional strength.
The rudder front spar was then positioned in its two pivots and the upper locating piece tacked to it to set the position of the bottom pivot on the spar. The rudder front spar was then removed and the two locating pieces final welded to locate the bottom pivot in position.
The rudder horn and tailwheel horns were then fabricated and welded to the rudder spar and the rudder spar installed. Next job is to route the rudder cables and build the linkage between the rudder and the tail wheel.
