Ik denk dat ik het antwoord hebt op de vraag hoe de afdichting gemaakt moet worden.
Ik kwam dit tegen op het internet.
http://www.jefa.com/rudder.htm
Tube and Gaiter.
The tube and gaiter sealing system is the most efficient method of providing a seal. The friction is almost zero, the sealing is 100% sure, and the gaiter will allow the shaft to rotate and bend freely. The system consist of an aluminium tube, which is bonded to the lower bearing and to which is clamped, via a stainless steel jubilee clip, a neoprene gaiter. The top end of the neoprene gaiter is clamped to the rudder shaft by a second jubilee clip. The gaiter is made to allow up to 90º of rudder travel (± 45º), without causing inelastic extension to the gaiter. It is desirable to take the rudder tube as high as possible for water security and at least 100 mm above the waterline.
The gaiter is in fact 100% waterproof and will show no signs of wear, even after many years of service. However it is possible for this to become mechanically damaged or torn, if materials are stored loosely in this area of the yacht.
Gaiters can also be supplied in unglued state with a special tube of neoprene glue. This is ideal for retrofitting as the rudderstock doesn't have to be dropped.
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