New Rudder Bearings

One of the jobs that had to be completed before the Round Ireland race was to replace Dinah’s rudder bearings. The original bearings consisted of a delrin ball inside an aluminium collar. The original bearings started to seize during the transat last year, and by the end of the season the steering was very stiff with a significant amount of “play” or lateral movement in the rudder itself.

Jefa, a Danish company specialising in bespoke steering solutions, were comissioned to produce a set of self aligning GRP bearings with needle rollers as the bearing surface rather than a simple ball and collar. More technical details of the solution produced by Jefa can be seen on their website.

Over a long weekend in April the old bearings were ground out of the hull, the new bearings were bonded in place, and then the new structure was carefully laminated into the hull to make it part of the hull structure itself and ensure the rudder loads would be spread appropriately.

The photo below was taken from inside the boat on a bright sunny day. With the rudder not yet fitted the sunshine illuminated the inside of the tube containing the lower bearing, and the light projected up to the new upper bearing fitted into the deck above. Bob did such a good job on the laminating it looked like a modern art installation!

The rudder itself now sits much closer to the hull underneath which is great as it reduces drag. Also, the lower bearing is faired perfectly flush with the hull outside, again to reduce drag compared with the original solution. When the rudder was refitted the improvement was immediately obvious. The rudder used to be stiff, and would not move easily. Afterwards, the rudder was swinging freely in the lightest of breezes. The boat now feels very different to sail, requiring only fingertip control in all but the heaviest of conditions. A huge improvement!