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6061 Aluminum boat part corrosion

I am making a new mast step for my sailboat out of 6061. It will be submerged in salt water a lot of the time. What is the best way to prevent corrosion?

Derek Smith
boat project - Houston, Texas
2006

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2006

Al 6061-T6 masts are usually anodized (conventional sulfuric acid process, sealed Ú Type II per MIL-A-8625 / MIL-PRF-8625 [on DLA] F). Apply an automotive or boat wax at least once a year.

Avoid contact with dissimilar metals to avoid galvanic corrosion Ú copper alloys are especially bad for aluminum. For unavoidable non-aluminum fittings and connections, use insulating pads (neoprene, PVC, Delrin, etc.) and anti-corrosive thread lubricants such as Tefgel or blue Loctite. Avoid any welding Ú it reduces strength and (generally) corrosion resistance.

Seal water out of the mast and 'partners,' and provide drain holes in the mast step. I'm not sure exactly how much is 'submerged in salt water,' but extra rinsing with freshwater afterwards is probably required.

For more details, see 'The Boatowner's Guide to Corrosion' ISBN 0071550194 (2001).

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.