Home /
Search 🔍
the Site

It's Tuesday 01/18/22 & your Q or A is Welcome.
Chime right in! (a "no registration" site)


"Cyanide Copper Plating on Zinc"

Finishing.com is made possible by ...
this text gets replaced with bannerText
spacer gets replaced with bannerImages

Current question:

December 19, 2021

Q. My experience is as one to go to space. I am a metal polisher and electroplater. I would like to express to all hobbyist and professional platers that cyanide copper is absolutely the only strike to seal old pot metal. My question is heat to each step -- 100 °F for cyanide, 80 °F for acid copper, 135 °F for nickel and 110 °F for hex chrome?

Is this correct? Also, does cyanide need to absolutely cover the front and back of pot metal to survive further steps? -Chase

Chase Kowalski

December 2021

A. Hi Chase. All of your temperatures are reasonable as design parameters, although Nickel is conventionally 140 °F, and the suggested temperatures for cyanide copper and acid copper may vary a bit. When you're in the general right range as you are though, holding the temperature constant within close limits is probably more important than trying to optimize it by tweaking it up or down a few degrees :-)

Yes, you need full copper coverage from your cyanide bath before you go to acid copper.

Luck & Regards,

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

Closely related Q&A's, oldest first:

November 12, 2009

Q. I am attempting to plate copper onto zinc. I am planning on making a solution of copper sulfate, ammonia, and potassium cyanide. My problem is an almost total lack of training in handling materials like this. I don't want to kill myself or any of our employees. I don't want to get cross with haz-mat folks.

But I have to get some copper onto this zinc.

Any suggestions as to how I can get some education/training on handling KCN and mixing, storing, handling the solution would be most appreciated. I have 2.5 kg of KCN coming within the next week or so and I need to have some emergency procedures and storage/handling guidelines already in place before it arrives.

Chuck M
antenna manufacturer - Utah

Hydrogen Cyanide Detector

Affiliate Link
(commissions from your purchases make finishing.com possible)

November 12, 2009

A. Hi, Chuck. I'm reluctant to say that you are approaching this wrong because I don't know all the facts, but ...

Very few OEMs do their own plating these days; they almost always farm it out to a plating shop. Unless your situation is really special, that's what I think you should be doing.

In turn, very few plating shops attempt to formulate their own plating chemistry; they almost always buy proprietaries. Even if otherwise, I'd suspect that they would order copper cyanide rather than trying to make up the solution from potassium cyanide. Plating is not a one-step process. Do you have tanks and chemicals for cleaning & acid activation? Do you have a wastewater treatment system ready?

You need a dedicated containment area for the cyanide; are you ready for that? You need HCN detectors; do you have them? You need a cyanide antidote kit; do you have it?

Again, I don't know the facts, but I'd strongly consider cancelling that cyanide order, and retaining a plating consultant to come in and advise. If his conclusion is that you should do plating in house, he may advise that you use a proprietary copper pyrophosphate bath or other proprietary instead of cyanide.


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

November 13, 2009

thumbs up sign Thanks Ted, I think I have canceled that order. I have spent the last couple of days reading up on cyanide handling and safety. Was really starting to regret going down that path. I am an electrical engineer that didn't do too well in chemistry. You probably saved someone's life with your advice.

I can make the plating tanks, that is no problem, we do lots of plastic fabrication. I need to put a coat of copper onto an antenna substrate we manufacture. It has to be done in house due to time constraints. This is to improve the solderability of the zinc as well as the conductivity.

Please recommend an alternate solution and a vendor of the solution if you would please.

Chuck McCown
- Lake Point, Utah, USA

"Electroplating and Electroless Plating of Copper and Its Alloys"
by N. Kanani
from Abe Books

Affiliate Link
(commissions from your purchases make finishing.com possible)

November 13, 2009

A. Hi, Chuck. You can probably get a proprietary copper pyrophosphate plating bath or other proprietary plating bath from a number of vendors, but one who specializes in it is EPI (Electrochemical Products Inc.) [a finishing.com supporting advertiser]. Contact them and I think they can help you.


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

Ed. note: Readers, we have many threads about cyanide copper plating, please use "cyanide copper plating" or terms related to your specific concern in our custom search engine.

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start 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:

Chemicals &
Consult'g, Train'g
& Software

About/Contact    -    Privacy Policy    -    ©1995-2022 finishing.com, Pine Beach, New Jersey, USA