Sacrifice on Windsong II

Just curious, do any of you remember your high school chemistry? Well I sure don’t (we had the cutest chemistry teacher — Mr. Sweeney — didn’t we Deb?)

So when the topic of “sacrificial zincs” came up, I had no idea what Bob was talking about.

As it turns out, the metal parts of a boat such as the propeller are eaten away over time by electric currents in the water (yes, there are electric currents in the water, but they won’t kill you). If left unchecked, the propeller will eventually disintegrate.

To prevent this from happening, you attach anodes to the metal parts, which are eaten away instead. In fact, they sacrifice themselves for this purpose, that’s where the term “sacrificial” comes from. They are made from a metal that is more “noble” on the periodic table. And it is noble to sacrifice right?

In southern waters, most boats have their anodes replaced every six months or so. As you can see from the following picture of our propeller, the anode was about half gone. Our feathering propeller is made in Australia and, as luck would have it, one of the importers for North America is in Miami, and they had the zincs we needed in stock.

So at this point we just needed someone to dive under the boat and replace the old anode with the new one. And it wasn’t going to be me!

Fortunately, there are divers on our dock several times a week, cleaning the bottoms of our neighbours’ boats. We asked one of them, Manuel, if we could hire him to change the zincs. He was glad to help. It took all of ten minutes and the job was done. Another zinc sacrificed!