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Beginner's plating questions

1995

I am currently trying to set up a small tank plating system for myself to plate non conductive items by using conductive graphite or silver paints. I want to do such things as golf balls, pagers, etc. in copper-nickel then gold. I normally am a brush plater so this is sort of new to me.

I have had success but a few small problems keep cropping up.  I am using 2 gallon 8x8x8 plastic tanks and phosphorized copper for anodes; through the anode is a titanium hook hanging on a copper or more recently a stainless steel bar. I keep getting some sort of corrosion on the anode between the copper and titanium that keeps any current from going through. Is there a way I can prevent this? Sometimes I will get no amperage and sometimes it will go to where it needs to be and slowly go to .02 amps or so.   It seemed after I brushed and re-drilled the hole in the anode and polished the titanium off, it worked well for an hour or so and then corroded again. I was using copper pipe to hang the anodes on, but it kept getting this thick scaling on it I assume from the acid copper I am using. I had to keep scraping this off. What could I use for anode hanging materials and the like? I have thought of just hooking the anodes to some building wire and clipping my lead wire onto it somehow. Any ideas?   Thanks a lot,  

Rob H [last name deleted for privacy by Editor]

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1995

Rob,

I used to copper plate circuit boards a long time ago. when I started my employment at this place, they could not plate out of their acid copper consistently. The amperage would fall and the voltage would rise. Come to find out the anodes were not phosphorized, but OFHC (Oxygen Free High Conductivity, I think).

If you use the wrong anode material in an acid copper (if you are using an acid copper solution), the anodes will become insulated and you won't draw any amperage. I have checked my training manual on acid copper, but it doesn't say what the anode hook material should be. I thought we used monel hooks, but I could be wrong. Please specify the type of copper plating solution you are using and the concentrations of the copper sulphate, sulfuric acid and chloride level. I can dig up other information or possible solutions. One more thing: Have you bagged the anodes? Let me know.

Matt Gazo

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Matt is certainly right that phosphorized anodes are correct for acid copper plating, but I'm not sure that I'd agree that the lack of phosphor is what is causing the particular problem you are experiencing. Lack of chloride sounds more likely if the problem is not simply bad contact, which would be my first bet.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005