Jan 132010

The keel is made from the SSAB super-duper Hardox 450 steel (remember the funny commercial about it?). Now this steel is not stainless, so it needs to be well protected from salt water. Usually you do this by painting it in epoxy. For the Journeyman keel this is probably not so good, since the steel will be flexing a little bit back and fourth when sailing. There is 4.5 tons of lead at the end of a 3.5 meter fin, after all… Ordinary epoxy will sooner or later crack in these conditions, which will lead to rust.

Now I found this nice Canadian propeller shaft manufacturer who has developed a protection paint for underwater steel. However, after learning that I would use it for something different than a propeller shaft they refused to sell it to me. This got me slightly annoyed, so thought I would play them a little trick. I contacted them through a completely different channel with a made up story about a propeller project, and was able to buy some paint that way. (Props to Alexander for helping out in this “scam” by the way :-)

Anyway, there are some points of the keel where it will be in contact with the supporting structure. In these points the paint will become scratched off over time, so we are putting small pieces of stainless steel in these spots. This means that as the paint is scratched off the exposed steel will be stainless and not rust.

In this picture your see the top of the keel with the mounting hole for the hydraulic cylinder that does the lifting (The keel can be pulled up from 3.8m draft to 1.8m for shallow harbors). The 4 stainless pieces that are being welded are the places where the keel will rest against the deck reinforcements when it is pulled up.

  3 Responses to “On the importance of being protected: The keel.”

  1. Hi J, What exactly is the picture showing? Cheers Stefan

  2. Isn’t that obvious :) ?

    I explained it in the post so that people who are not reading the comment will see it too.

  3. Yes indeed. And the most recent post show the whole shabang!