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Proper Spelling of Iridite / Iridite

2005

I am a Drawing Checker for the Dept. of Defense and there has been some controversy in reference to the proper spelling of "Iridite" finishes. (MIL-C-5541)

It is currently under scrutiny as either being spelled "Iridite" or "Irridite".

Thanks so much

Joseph R Matthews
Dept of Defense - Maryland

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It's a trade name, so the trade name owner gets to dictate the spelling :-)

And Macdermid says it's 'Iridite'.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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MIL-C-5541, possibly a revision F that calls out a no Hex chrome. These standard products do not comply with this stipulation. There is a hex free chrome that meets this specification. I suggest before you put anything on the drawing you check to see as to what actually is the newest requirement of this specification. Again I am only going on what I have heard about the newest requirements ( Euro Union) so if I am wrong I'm sorry. If you want info on the hex free Iridite replacement visit my web site.

Drew Nosti, CEF
Anodize USA

Ladson, South Carolina

2005

As I understand it there have been changes to

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2005

"Iridite" (one 'r') is a WHOLE FAMILY of hexavalent chromium chemicals for converting a host of materials, NOT LIMITED TO ALUMINUM, to a chromate coating. "Iridite" is a registered trademark of MacDermid - formerly Allied Kelite prior to MacDermid purchasing AK. Iridite 14-2 is for doing basic chromate conversion coating on aluminum, but there is an Iridite for yellow chromate on silver, several for zinc, Iridite 15 for chromate on magnesium, etc. Bottom line: putting "Iridite" on a drawing doesn't make sense - it's a trade name and not even a unique process.

What's wrong with a specification such as MIL-C-5541, AMS2473 , or the appropriate ASTM spec?

Also, regarding Mr. Nosti's response, the only spec that's been revised [yet, as of 2005] to include a non-hexavalent chromate for aluminum is MIL-DTL-81706 [on DLA] which includes a provision for BOTH the conventional hex chrome bearing as well as another for non-hex. The associated QPL-81706 [on DLA] which will list qualified products for both hex and hex-free hasn't been released ( NOR HAS MIL-C-5541 ).

Milt Stevenson, Jr.
Syracuse, New York