Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Where the
world gathers for metal finishing
Q&As since 1989

-----

Can I anodize on top of existing anodic film

2004

Hi There,

I have a component that has already been anodized,type ii sulfuric. The material is 6063. My question being, I have had some rework performed,and would like to anodize the re-worked areas. Can I just anodize the whole thing again,on top of the old anodizing? Or will I have to strip the old anodizing off and start again.

ps, Masking the old anodizing is not a practical solution.

Thank you for time Regards,

Steve Power
Helicopter Engineer - Nelson, SI, New Zealand

NO !

For example, Type II anodizing is used as a maskant for Type III selective anodizing.

You can take a part out and look at it, keep it wet, and restart anodizing, but once it starts sealing (even in cold rinse water) there is NO re-starting.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2004

steve,

the anodizing will only 'take' on bare/de-oxidized surfaces. just be careful that during the process, the existing anodizing is not chemically removed. why not just strip and anodize again? tolerances? surely that's the safest?

Michael Georgiadis
fishing reels - durban, south africa
2004

(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully 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 might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: