-- The Home Page of the Finishing Industry
A website for Serious Education, promoting Aloha,
& the most FUN smiley you can have in metal finishing

topic 1284

Anodizing and dyeing alloy 6262


I would like any feedback on the following anodizing problem: We experience a phenomenon I'm told is dye precipitation when we anodize and color alloy 6262 T8 and T9. It manifests itself as dark blobs, primarily on surfaces machined perpendicular to the long axis of the grain structure. We have seen the phenomenon occur after coloring in azo and anthraquinone dyes. Testing I've done indicates the problem is influenced by bath age (possibly chlorides) and tooling material choice (Ti vs. Al). Azo dye precipitation appears to be influenced more by bath age than tooling material. The opposite appears to be true for anthraquinone dyes. We do not see the phenomenon on any other alloy. Any ideas what we may be seeing?

Charles H [last name deleted for privacy by Editor]
metal finishing


I am a 17 year old metal student who is looking to give my aluminum projects an extra flair by Anodizing them in a color. The only problem is that I don't know the Dyes to use. I have researched the process and I am only lacking that information, if anyone could help me I would be very thankful. I would like to know what dyes to use to achieve the color green.

Thank you.

Nick [last name deleted for privacy by Editor]

RIT Dyes


Hi, Nick

Ed. note: For a student project, RIT fabric dyes =>

are available inexpensively, and will prove fine. Professionals can obtain anodizing dyes from a number of vendors including U.S. Specialty Chemicals.


Ted Mooney,
Teds signature
Ted Mooney, P.E. RET
Pine Beach, New Jersey



, I have sold my inheritance for $35.00. Try to find a copy of Graham's Electroplating Engineering Handbook, it had some dye stuffs listed. (I didn't have the room for it anyway=sour grapes). It may be in Durney's edition, but I can't put my finger on it right now.

tom pullizi signature
Tom Pullizzi
Falls Township, Pennsylvania


How do I find the answer for 6262 Anodizing and dyeing alloy ?

Jenifer Villanueva
- Dekalb, Illinois, USA

Ed. note: Hello Jenifer. It's a public forum. If anyone anywhere offers an additional suggestion besides consulting the Electroplating Engineering Handbook, we'll print it. Are you having an identical problem to Charles H? If your problem differs, please give the details of your own problem because maybe someone who couldn't help Charles with his problem can nonetheless help you with yours. -- Ted

This public forum has 60,000 threads. If you have a question in mind which seems off topic to this thread, you might prefer to Search the Site

ADD a Q or A to THIS thread START a NEW THREADView This Week's HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2017     -    Privacy Policy
How Google uses data when you visit this site.