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How to darken zinc plate and galvanized materials
Q. My builder just put up a new fence for me with zinc plated hinges and a galvanized thumb latch on top of the gate. Does anyone know if there is anything I can put on these parts to darken them, for they really stand out and look terrible. Thanks so much!
Sharon Ballinshobbyist - Yountville, California, USA
2004
publicly reply to Sharon Ballins
A. You can use 200 grams iron chloride/1 lit water solution!
Good luck!
- Cerovski vrh Croatia
publicly reply to Goran Budija
Q. Where does one obtain iron chloride?
John Welch- Des Plaines, Illinois, USA
October 8, 2008
publicly reply to John Welch
A. Hi, John.
Iron chloride is just another name for ferric chloride ⇨
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
publicly reply to Ted Mooney
Q. I have seen gal beams left under gum trees for a couple of months, they get stained and look like a rusty colour; I am after this effect in a warehouse style loft to make it seem older. Ideally I would not coat the steel at all until it rusts and then clear coat over the rust.
Any help appreciated
- Sydney NSW Australia
February 2, 2012
publicly reply to Brett Houssenloge
A. Hi, Brett. The purpose of galvanizing is to stop steel from rusting; so you should use plain non galvanized steel if you want rust. I don't know if it's possible to get a nice mottled look on galvanized steel quickly, but you could test ferric chloride ⇦ this on eBay or Amazon [affil links] or a patina made for zinc ⇨
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
publicly reply to Ted Mooney
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"User's Guide to Hot Dip Galvanizing for Corrosion Protection in Atmospheric Service" by NACE (1997 only rarely avail.)
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Q. Thanks for the help; the engineer has requested that all of the steel, etc., be Hot dipped; I just wanted to take the edge off the new look and of course not damage the protection of the hot dip. Maybe I will spray the showing surfaces per the previous suggestion. Should I wash it off once the effect is reached?
Cheers and thanks -- Brett
- Sydney NSW Australia
March 6, 2012
publicly reply to Brett Houssenloge
A. Hi. If using the commercial patina, follow its instructions. I doubt that it is supposed to be rinsed though.
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
publicly reply to Ted Mooney
Q. Here we need to apply a darkened (dulling) aspect on a hot dip galvanized steel. The problem is I wanted to to it without the usual five steps (acidic activation, cleaning, darkening, cleaning, passivating). Is there any way we can do it with less steps or products?
Paulo Moch- Sao Paulo, Sao Paulo, Brazil
August 1, 2014
publicly reply to Paulo Moch
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