Above in the cockpit, the edge can be left standing up, but underneath the hull I file the edge off, so it's flush. The rudder should be gap-free in any angle against the hull, even if the rudder is turned 10° to the sides. Usually this works only if the rudder stem is perpendicularly to the hull. With a tail discharge of 11° that would mean, that the shaft has to stand  11° from the vertical line also. When the rudder positioning is completely off, you get an elevator steering, dig, dig, dig.
The hull was angled in the tail region for this reason at the amidships line in the computer (something I implemented  last year).

To get the correct alignment of the rudder bearings, a rudder template is built. It consists of an axel with three blades mounted on it. Each of the blades simulate the position of the rudder in that angel, so that the points lie all on the same plane, perpendicular to the axle. These points are distant from the axle according to the rudder length above. One blade is amidships, the other two are rotaded for instance 35° - actually the maximum rudder angle, while sailing. According to this rudder template the lower bearing is grinded down to the  the model template rests against the hull.

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And if the rudder lies laterally somewhat diagonally opposite the keel fin, I rather bend the rudder axle, to align rudder tube perpendicularly, for instance file the bearing somewhat differently . With this boat however, that was not necessary.


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