finishing.com -- The Home Page of the Finishing Industry

-----

Gun Blue Causes Discoloration of Cadmium Plated Aluminum Part

My company makes fiber optic connectors for the military. Recently we are experiencing a problem with our aluminum parts coated with cadmium. If we get a scratch in the cadmium finish it will not pass through a QC inspection so we treat it with a little bit of Perma Blue Liquid Gun Blue ⇦ on eBay or Amazon [affil link] . In the past it has not been a problem as the discoloration from the scratch is hidden by the Gun Blue. Recently however the area of the Cadmium plating where the Gun Blue is applied is is becoming significantly darker than the rest of the cadmium finish and it also does not pass thru a QC inspection. Any ideas what could be causing this discoloration of the cadmium finish where the Gun Blue is applied to in recent weeks. Thanks for your help.

Sean Cahill
Fiber Optic Cable Assembly Manufacturer - Naugatuck, Connecticut, USA
2006

? I'm having a hard time understanding how BC gun blueing is an allowable repair for a scratch! ?

Bill Grayson
metal finishing - San Jose, California, USA

No dead threads! If this page isn't already on the Hotline your Q, A, or Comment will move it there.

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: