Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ

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

The authoritative public forum
for Metal Finishing since 1989
-----

Zinc Contamination

After my parts have been zinc plated and are fed through a feed bowl they we are seeing a black substance form on the parts and the feed bowls. The bowls are stainless steel and we are feeding approx. 40,000 to 50,000 parts in a 8 hour shift. The part measures 1/2 inch square and is .059 inches thick and are flat. The black substance has a tendency to stop the parts and cause or automated machines to stop moving the parts. Is this a nature of the plating or can this black substance be eliminated? It seems as though it comes and goes.

Skip Shildmyer
PTL Mfg. Inc. - Belleville, Illinois, USA
2003

Most zinc plated parts are chromate conversion coated. This coating is a very thin gel but not abrasion resistant. If the parts do not have enough drying time, or if the chromate coating is thicker and thinner you might see this problem come and go.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

(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: