Metal finishing Q&As since 1989

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Galvanic Concern: repairing anodized aluminum railings with steel L-brackets

I live in a building that is surrounded on three sides by saltwater. Exterior decks and balconies have aluminium railings. Because of the lack of proper maintenance (painting), "salt air" has corroded some of the braised connections between horizontal and vertical members of the railings. On-site management wants to use bare steel L-brackets with common steel screws to reattach the loose members. Aside from the unsightliness, I have concerns that the use of dis-similar metals with cause corrosion. Please provide a professional opinion about the proper way to reattach these aluminium members, and tell me whether the use of bare metal L-brackets and steel screws is a mistake.

Thank you for your prompt attention.

Larry Celey
- Miami, Florida, USA
2002

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Hi Larry. This one doesn't resolve to professional opinions. You want them to do it properly, and they only want to do it down and dirty. Galvanic corrosion is hardly a significant issue to worry about if things are as bad as you make them sound. Yes, the presence of steel will accelerate the corrosion of the aluminum, but if the corrosion is so bad that the welds have already disappeared and the verticals are detached from the horizontals, there's not much left to protect. The "right" answer is surely new railings.

But you only get a 'professional opinion' by hiring a metal finishing consultant to visit the site and investigate; you can't get a professional opinion from strangers, for free off the Internet :-)
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002