Pyrophosphate and non-cyanide copper strike/plating process problems & solutions

A. Hi David. The SDS or technical data sheet may tell you a little about proprietary non-cyanide baths, but they are proprietary so the info will be partial at best. The SDS reveal that at least some contain phosphoric acid or phosphorous acid.

The complaints you read on this page about non-cyanide baths are surely true, but tell us about your situation please :-)

I don't think "unreliable" is the exact descriptor because copper pyrophosphate baths were for a decade or more the state of the art in printed circuit board plating way way back when, as well as used for plating directly on steel components. I was an equipment engineer rather than a process guy back then, but I regularly visited RCA Camden's circuit board shop back, and also visited Hughes Tool in Houston, which both used M&T Chemicals' pyro copper baths. Luck & Regards,


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

A. Hi again. Popat is welcome to reply but I don't know if he will, and I doubt that he would know whether a proprietary product he used contained MSG.

If you have a formula for a home-brew copper pyrophosphate, maybe you should try it rather than worrying about how much maintenance it needs in a production environment. Hobbyists have two big advantages over production platers --

1. They only have to satisfy themselves, which is an awful lot easier than guaranteeing the satisfaction of a broad spectrum of people.
2. Production platers have to operate an equilibrium process and hobbyists don't. By this I mean when a plating bath is in production, it has to have the same concentration of everything constantly, after ten parts are plated and after ten thousand. A lot of the adjustments that people talk about refer to exact and timely replenishments rather than set-up for a short one-time run.

What substrate are you intending to plate onto? If steel, nickel striking then acid copper plating is probably the easiest and lowest tech answer. Good luck. Regards,


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

A. HELLO TRENT !
I WAS USING NON-CYANIDE COPPER STRIKE IN YEAR 1986.
EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser] E-BRITE 30; WAS WORKING GOOD BUT YOU HAVE TO UPDATE YOUR CHEMISTRY EVERY DAY.
I WAS PLATING COPPER ON ALUMINUM PART (SUBSTRATE): ZINCATE THEN ALKALINE ELECTROLESS NICKEL STRIKE, NON-CYANIDE COPPER STRIKE & ACID COPPER PLATE.

A. Hi Trent,

I've run both pyrophosphate strike and the E-Bright copper mentioned. Both work, both are expensive, and both are a pain in the A. If you absolutely had to get rid of cyanide ... but since you don't, I'd advise you stay with a good ole' cheap, easy cyanide strike.

A. Hi Dadong. Although the non-cyanide copper solution perhaps could be used for a heavy buildup, Jeffrey tells us that it's an expensive, pain in the A way to go ... so it may be better to use it just as a strike and then do heavy acid copper plating.

Regards,

A. Hi Sergio,

I run just one cyanide copper bath for both plate and strike. Blistering could be from a lot of different things, but here is where I would look first. Are your castings any good? We run Zamac 3 alloy and get occasional porosity and cold shuts that will cause blistering.
Keep your strike pH down to <12. I have seen blistering when strike pH gets too high. Of course you need to check your cleaning cycle.

Electroclean
Rinse
Acid salts
Rinse
Strike

Strike parameters (mine anyway):
Temp 140 °F
Approx. 25 ASF for 5 minutes (I don't go in "live")
[Cu]= 8 oz/gal
[CN]= 4.5 oz/gal
pH 10-12


Hope this helps.

!! Hello... Dear All
Mr.Trent...
I have been using a formula for zinc die casting materials. If you try this formula you will get rid of the cyanides problems.I have used this formula for 2 years. At first we had some zinc contaminations. But we add some process in plating facility and we succeed this. Maybe we are the only ones to use this process in the plating world. I hope Mr. Ted Mooney views positively this formula.
FORMULA:
NICKEL SULPHATE (90 gr/lt)
BORIC ACID (15 gr/lt)
AMMONIUM KLORÜR (25 gr/lt)
SODIUM sulphate (90 gr/lt)

pH RANGE: 6-6,5
Current Density:1,5-2,5 A/dm2 (depending on your part's geometrical shape)

BUT! (ATTENTION!)
IF YOU RUN THIS PROCESS, YOU HAVE TO RUN CONTINUOUS DUMMYING. IF YOU DON'T DO THIS YOU WOULDN'T CONSIDER THIS PROCESS BECAUSE YOU WILL HAVE SOME TROUBLES ESPECIALLY ZAMAC CONTAMINATION.

TRY, AND PLEASE RETURN A REPLY TO ME.

GOOD LUCK.

Thanks, cousin Alaattin.

Regards,

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

? Are you using this as a strike bath before bright nickel or is this the only nickel you are applying to the part?

Gene Packman
- Great Neck, New York
2005

!! Hello again.

I use this process instead of cyanide copper bath. So, I eliminated cyanide from plating facility. If I say our process way ;1-hot degreasing 2-ultrasonic degreasing 3-electrical degreasing 4-acid pickle 5-HARD NICKEL (I mentioned and to give formula bath before mail. I use Instead of copper cyanide bath. High ph nickel bath.) 5-Bright nickel.

I hope to help somebody especially to love and want non-cyanide life.

A. Hi Snehal. Are the diecastings individually inspected for absence of cold shuts and other defects before plating? Your process sounds okay, but even a good process will leave you with a blister at every cold shut.

Have you broken some of these blisters and observed what material you see on the substrate and on the underside of the blister? Thanks.

Regards,

A. Hi Snehal. If some of your platers generate acceptable parts and some generate unacceptable parts, what you must do is simply to have only the good platers process your parts. You probably can't solve the problem for the poor platers anyway, and it might even be unethical to try to learn the trade secrets of your successful platers and pass them on to the others.

But, as I suggested, I think it is more productive to examine the substrate and the underside of the blisters to determine at what stage the problem develops than to just start changing things and hoping for improvement.

There may be tests for porosity and cold shuts, but I am not familiar with them. My only experience is in examining diecastings by eye to look for problem areas. The intention is not so much for the purpose of 100% inspection as to determine whether the quality of the diecastings is good enough, and improve it until it is consistently good enough. Best of luck.

Regards,

A. Hi.
The acid salt (as per Trent Kaufman process) for activation prior to cyanide copper plating will definitely help a lot. Make sure it is formulated for zinc castings.

Good Luck.

A. Hi again. The overall thrust of your 4 postings seems to convey your conviction that lack of cyanide plating is the problem. There is no doubt that cyanide makes day-to-day operation cheaper and easier, but two readers have reported success with alkaline non-cyanide copper, and another has reported success with a nickel strike in lieu of copper. I have also seen the nickel strike successfully used in two facilities, but I was not involved in the chemistry of it. I have twice suggested that you scrape off the blisters and learn at what stage in the process they occur, but you haven't gotten back to us on that. I'm not quite sure what information you are asking people for at this point, but good luck.

Regards,

A. Hi Carmelo. I don't think the solution composition is a problem. In fact, I'm not even sure that there is a problem except perhaps for expectations of greater productivity than is practical. A plating rate of 0.5 A/dm2 (5 Amps/sq ft) for large production-sized plating barrels doesn't strike me as ludicrously low.

Was the pilot run done in production barrels filled only to 10% capacity? If so, you had 10X as much barrel wall area for the current to pass through per kg of production. If the pilot run was done in lab barrels, the anode centers were probably smaller for less solution resistance and still the barrel wall area compared to parts area was much more favorable.

But you might look at the hole size in the barrels as it's possible that it's too small. What is the part size/shape and the hole size? Are these new barrels where you are confident that the holes aren't partially peened shut?

Regards,

A. Hi Tim. I know that EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser] offers a wide range of non-cyanide alkaline copper plating and striking solutions, but I am not personally familiar with any non-proprietary bath of that sort except for possibly copper pyrophosphate.

Luck & Regards,