HOME FAQs BOOKS JOBS: Help Wanted Suggestions      you are here: Hotline/Forum => Letter 40620

---

Test to check clear Iridite coating

++++++

Is there a method to test if aluminum parts have been coated with clear Iridite?

Chem. or electronically

Joseph J. Maschin
- Fort Lauderdale, Florida, USA

---

++++++

Just trust the word of your plater.......kidding with you...

I don't think anyone has come up with any test for this clear iridite verification.

How about conductivity test which is required in clear iridite. But again this test itself does not tell you much from yellow to clear iridite. I am only talking about my experience.

Thanks

Hemant Kumar
- Florida, USA

---

++++++

Iridite is a trade name for generic chromate csonversion coating for aluminum. Spot test kits are available from the supplier of the product. Also, non-proprietary formulations are available for detecting the prescece of the chromate coatings.

Robert H Probert Robert H Probert Technical Services Garner, North Carolina Editor's note:        Mr. Probert is the    author of Aluminum How-To / Aluminio El Como

---

++++++

"Clear" chromate coating is a myth. If there in NO color, there is NO coating. The color may be faint, but if there is a chronmate coating, there will be color.

"Clear" chromate is as real as the Emporers new clothes.

Jeffrey Holmes, CEF - Spartanburg, South Carolina

---

++++++ Mil-C-5541 [link is to spec at TechStreet]Class 3 "clear" (but it does not have to be to meet the spec) to the naked eye will increase salt spray, indeed, is frequently required to pass 168 hours salt spray. It is not a myth. It can be unseen by the naked eye and you have to submit a drop test to prove that it is there.

Robert H Probert Robert H Probert Technical Services Garner, North Carolina Editor's note:        Mr. Probert is the    author of Aluminum How-To / Aluminio El Como