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Difference between gold Alodine and gold chem-film?

We are a machine shop. One of my customers is requesting Gold Alodine. My local platers does Gold Chem Film. Are Gold Alodine and Gold Chem Film the same?

Jeff Carley
- Valencia, California, USA
2003

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Chem Film is the current name for a chromate conversion coating on aluminum. There are shades from clear to light tan to yellow to gold to a burnt orange. Alodine is the specific name for one of the two best known products. Iridite is another. (there are literally dozens not counting home brews)

James Watts
- Navarre, Florida
2003

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Alodine = Iridite = Chem Film = Chromate on aluminum = MIL-C-5541. They're all the same. Alodine is Henkel's brand name for a variety of chromate products, primarily for aluminum. The military spec for these products refers to the coating as chemical film.

Milt Stevenson, Jr.
Syracuse, New York
2003

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Yes, But, Milt. Jeff and some other readers may not realize what you know, that for a chem film = chromate on aluminum to comply with Mil-C-5541 the particular chemical mixture must be on the QPL-81706 [on DLA] list.. Alodine and Iridite are on the list, as are a lot of others; but some small vendors' products and all home brews fail to be on that list and therefore cannot be used for Mil-C-5541

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