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Brownish Red contamination on Yellow Zinc Chromate

I am seeing a brownish - red substance leach out from seams between welded components.
Material is AISI 1006 -1012

Need to identify, and determine best way to clean.

Thank You,

James Polidori
Consumer - Rochester, New York, USA
2007

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I hate to be the one to tell you, but it sounds like rust. What else could it be? Neither zinc nor chromium have any common compounds that are red. There really is no way of cleaning it - you could wipe the stains off with an IPA soaked rag, or something, and hope for the best.

It is very common, even with ample rinsing, for finishing solutions to "hang up" in the void spaces in welds, only to bleed out some weeks or months later. Platers who wish to avoid this blow out these spaces with compressed air, spray some DI water in under pressure, then blow out again.

I'd have a talk with the plater.

Dave Wichern
Consultant - The Bronx, New York
2007

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Also talk to the designer. Capillarity of liquids between and behind tack welds poses a perpetual corrosion risk. Continuous welding to seal the joint may be a better investment than extraordinary rinsing, which is difficult at best and won't keep out rain, wash water, coolant, etc.

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.
2007