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Chemicals for gold brush plating

I want to brush plate gold on some large flex circuit boards. Since it is a large area I want to plate and a large quantity, I would like to make my own solution in house or find a supplier that has good pricing. I am interested in finding the chemicals that will be the safest to use and most cost effective to use.

Deborah Johnson
Electronics Manufacturer - Fontana, California, USA
2004

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The overwhelming majority of professionals do not attempt to make their own plating chemicals, Deborah. All the more so when dealing with precious metals where the majority of the cost is in the metal itself anyway. All it takes is a few rejects and you've wasted more money than you can ever recover.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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Brush plating large quantities of anything is a joke. rack or barrel is the only way to go.

Nearly all brush plating gold solutions are cyanide based.

I am sure if you are going into production in any kind of quantity DEP will want to see your waste treatment system.

Don't believe those vendors who say that brush plating is environmentally friendly and DEP has no objections. If DEP see a cyanide rinse on the floor, they will object. So will your wallet.

Steve Clark
- Belfast, Maine
2004

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To say brush plating of large quantities of anything is a joke completely misses the reason why brush plating is used. Brush electroplating is used when selective areas of larger components require an electroplating coating. This selectivity is important because it can greatly reduce masking requirements and it allows for plating of parts that are too large or cannot tolerate submersion in an electroplating solution as was suggested when referring to rack and barrel plating.

While most gold brush plating solutions are cyanide based they can be used with a high degree of safety. These solutions are used at room temp. and in most cases do not require large volumes of chemicals to be used. This is also helpful in the rinsing and waste control of the process. Disposal of the gold solution and rinse is done using an outside service that will refine the gold in the waste and in many cases, pay you for the recovered gold, less expenses.

Finally it is pretty obvious that cyanide of any kind on the floor is a health and safety concern that is easily remedied and not at all exclusive to the brush plating process.

Chris Helwig
- Valencia, California, USA
2004