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How to remove heavy calcium deposits from aluminum pontoons?


Larry Molstad asked:

Which of your products can be used to remove heavy calcium deposits on pontoons?


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IN SUMMARY,with the limited technology available today, the best steps to remove heavy calcium deposits on your aluminum pontoon are:

1. Use sand paper until you get close to the aluminum
2. Use Algex to remove the small amounts left on you aluminum pontoon
3. Protect you and extend the life of your aluminum by using Alumetron and VS721


Unfortunately none of our products are strong enough to remove heavy calcium or calcite from aluminum without damaging the aluminum and we are unaware of any other product that will accomplish what you are after. We have been working on this problem but still do not have a solution.

With the current technology, the best way to remove heavy calcium growth is with sand paper, until you get close to the aluminum, then you can use Algex to remove the small amount left in the grain of the aluminum. Most aluminum boats and pontoons are built with the mill finish grain running horizontally.

When sanding, it’s important to sand with the grain and not against it, otherwise you will see the sanding marks in the aluminum. I suggest that you use a long board sander in a horizontal back and forth motion or get a pneumatic linear buffer and use it in a horizontal method. The buffer will save you a lot of labor and shoulder pain. You may want to start with an aggressive grit until you get close to the aluminum and then I recommend that you switch to 600 to 800 grit wet sandpaper so that if you accidentally sand down to the aluminum the sand marks will be in the same direction as the grain and the marks will be about the same size as the mill finish grain.

After you get the aluminum clean and bright again, I suggest that you protect it properly so that you don’t have to go through this again. You can protect the aluminum with Alumetron, which will last for 5 years or more and with VS721 every spring. If you don’t maintain your aluminum boat and keep it clean, you will be replacing it much sooner than you wish.

Thanks for you question.

Captain Aurora
Richard Kittar

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