Where the
world gathers for metal finishing
Q&As since 1989


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White Rust / Wet Storage Stain on Chain Link Fence

I have a problem with white rust on a large volume of chain link fence. What causes white rust (the manufacturer is making more for me)? Anything I can do to remove the existing white rust?

Greg Jendreas
1998

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WHITE RUST ON LINK FENCE IS GENERALLY REFERRED TO AS WET STORAGE STAIN. AND IS NORMALLY ASSOCIATED WITH GALVANIZED MATERIALS. THE GRAY DEPOSIT IS FORMED BY ACCELERATED CORROSION OF THE ZINC COATING WHEN CLOSELY PACKED, NEWLY GALVANIZED ARTICLES ARE STORED UNDER DAMP AND POORLY VENTILATED CONDITIONS. CONTACT THE AMERICAN GALVANIZER'S ASSOCIATION FOR PUBLICATION MA-10 FOR FURTHER INFO.

ed weiss
1998

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We have a periodic problem of rusting on the sheared edges of galvanized steel. What is causing this? It's not on all runs. Can anyone offer solutions as how to protect the edges of sheared metal?

I would appreciate any help!

Walt McLeod
- Cambridge, Ontario
1998

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Hi, Walt. Unfortunately, plain steel rusts and quickly. Hopefully the zinc on the coated areas sacrifices itself rather than letting the sheared edge rust, but this is an "iffy" thing as you have discovered.

If it is practical to apply Cold Galvanizing Compound / Zinc Rich Paint, that is the best answer. If the sheared edge it to go without protection, rolling the edge under may be the only reliable approach. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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2000

DEAR SIRS,

I AM SERVING IN NEW INDIA ASSURANCE COMPANY. I HAVE COME ACROSS A CLAIM IN WHICH GALVANISED IRON SHEETS IN COILS WERE FOUND WITH WHITE RUST FROM TOP AND BOTTOM SAY ABOUT SIX INCHES THROUGH OUT. THIS WAS CONTAINERISED CONSIGNMENT AND CONTAINERS CAME FROM CHICAGO AND WERE NOT VENTILATED. WHAT COULD BE REASON FOR DAMAGE, AS THERE ARE NO SIGNS OF WATER INGRESS.PLEASE GIVE ME SUITABLE INFORMATION AND OBLIGE.

WITH KIND REGARDS

ASHOK M GAWARIKAR
- new panvel Maharashtra India

Problem is decomposition/ failure of zinc coating on small metal parts in storage cabinets, possibly linked with contact with timber treated with tanilising material, or in contact with polystyrene or other plastics. It is thought that products in tanilising treatment or vapours from polystyrene / other plastic is reacting in some way.

Russell Genese
- New Zealand
2000

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I am living in Cape Town South Africa and we have recently experienced that white rust was forming on a powder coating job that we did two and a half years ago. The fence cannot be removed and some remedial work is necessary on site. Any suggestions on how to treat the problem?

Andre de Wet
epoxy coater - Cape town South Africa
March 19, 2009