S.S. prop shafts will carrode in a low oxygen state. This is called Crevious Corrosion. However, most shafts today are made from a material called AQUAMAT. This material comes in several grades like S.S.(304,316,etc.). The most common for prop shafts is Aquamat 19 and Aquamat 22. This material is much stronger then S.S. and more resistance to corrosion then S.S. with the grade 22 being the strongest.
The bronze shafting material is TOBIN BRONZE and is hard to come by. This is not marine bronze. Many boats today come with Auqamat shafting. If you keep your zinc's in good repair, this shafting material will last the life of your boat.
glen@srssystems.com
Prop Shafts
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