I saw a boat that was only about 3 years old with a rudder split from ice. Some people have holes drilled in their rudders at the bottom they drill out in the fall and then epoxy closed before launch. My boat is not out of the water in the winter, so I have not had this issue.
A buddy with a C&C 35 MK II had rudder issues and brought the rudder home as a project. He managed to cut a big section of skin off, scoop out all the wet foam, fill the space with an epoxy mix, and epoxy the skin back on. Also note you can just buy a new rudder 😉 Joe Della Barba Coquina C&C 35 MK I Kent Island MD USA
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