No registration, no passwords; no pop-up ads -- just aloha, fun, & authoritative answers.
As an eBay Partner & Amazon Affiliate we receive compensation for qualifying purchases.
Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site
pub  Where the world gathers for
plating, anodizing, & finishing Q&As since 1989





-----

Cloudy CADMIUM Plating




We are currently experiencing a cloudy type deposit at normal current densities in a cyanide cadmium rack bath. All bath parameters are within suggested guidelines. We do have zinc at 351 ppm and copper at 24 ppm, but don't feel that is the problem, because our bbl tank has comparable contaminant levels and isn't showing the same problem (we bbl plate zinc die castings). A 1/2 amp / 5 hull cell panel looks great but a 1 amp / 5 looks terrible. We have tried HCD dummying and dilution without much help. We don't appear to have rectifier or buss problems. Any thoughts or ideas?

Jon Phillips
plating shop - Mpls., Minnesota
1999


Jon, dummying should be done at low current density with a corrugated dummy cathode. It is probably two problems. I don't like the copper at 24 ppm and it could be organic contamination as well. Are you using a proprietary cadmium brightener? Virtually all have a very small amount of nickel. All proprietary cadmium brightener suppliers have the brightener available with the nickel left out. Have you contacted your vendor and asked them for help? What temperature is the bath operated at? Have you tried adding some 35% Hydrogen Peroxide to the Hull Cell? (organic trouble). What is the analysis-very important! Bath may just need additions.

Bill Hemp
tech svc. w/ chemical supplier - Grand Rapids, Michigan
1999


Refrigerate 1 gal. of your cadmium solution overnight. Next morning carbonate should have precipitated out; do a hull cell test to see if the problem has been solved.

Gary Patigler
- Richmond, California
1999




(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:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"