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

HomeFAQsBooksHelpWantedAdvertiseForum
topic 9802

Film Formation on Black Anodize


(2001)

My shop is having a problem with a whitish film formation on our black anodized parts. If the parts are reworked, the film does not appear. The film forms every time with the first generation work and changing/varying the etch, bright dip, desmut etc. has very little effect. Any ideas?

Victor Waldman
- Naugatuck, Connecticut


(2001)

Are you stripping with chromic-phosphoric and running a chrome-free desmut? There are some stains and problems that only seem amenable to removal in chromic acid.

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


(2001)

We are a chrome-free shop so we don't even have the option of trying your suggestion. {:(] The film formation is less if we run the parts with NO pre-treatment, though not as film-free as the reworked parts.

Thanks for any feedback.

Victor Waldman
- Naugatuck, Connecticut


(2001)

Have these parts been finished in a vibratory system? The ceramic stones create a powder that, if not rinsed off completely when wet, will stick to the surface. This dust is hard to see on bare aluminum and very difficult to remove. The anodic coating will form under this powder, leaving a white residue on the finished part. Stripping seems to remove it. Ultra sonic cleaning is fairly effective in rewetting and removing the dust before anodizing. The best solution is to completely rinse the parts after vibratory finishing.

Chris Jurey, Past-President IHAA
Luke Engineering & Mfg. Co. Inc.
supporting advertiser
Wadsworth, Ohio

luke engineering banner


(2001)

Do you find this situation after the dying or after the seal? We have found if our seal dies prematurely, a white film will form.

Bill Smith
anodizing shop - Trinity, North Carolina



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 finishing.com     -    Privacy Policy
How Google uses data when you visit this site.