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Need Help with Plating Polished Nickel over Nickel (Replate)

Need a process to run production numbers of rejected material that has been chrome stripped and then polished so that I can run it nickel over nickel. Everything that I have tried so far is a hit or miss. We have tried different activators and such. I have the adhesion but the plating is not very good with stains and such. Any help with chemicals and a process would be great.

William Sklavenitis

2006

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2006

WILLIAM !

You can try following step to plate nickel over nickel.
1 soak
2 Electroclean -DIRECT current
3 RINSE
4 RINSE
5 POWER ACID -10% SULFURIC ACID - DIRECT CURRENT
6 RINSE
7 RINSE
8 WOOD NICKEL STRIKE
9 RINSE
10 BRIGHT NICKEL PLATE

TRY IT . GOOD LUCK

Popatbhai B. Patel
electroplating consultant - Roseville, Michigan

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Hi William,

Mr. Patel's answer is correct, but the staining will always be a problem with nickel over nickel unless you have perfect cleaning (haha). You could try a barrier layer between the nickels such as acid copper if you have it.
Make sure you have no bare steel showing or the copper will form a non-adherent immersion layer.

Remember to activate and good luck.

Trent Kaufman
electroplater - Galva, Illinois
2006

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This is difficult! I have used the following process successfully.
1. Loosen heavy oxide in a mixture of 13 oz/gal potassium permanganate ⇦ this on eBay or Amazon [affil links] + 13 oz/gal sodium hydroxide for an hour or two at 190 °F. Probably not necessary in your case.
2. Cathodic in a cyanide cleaner, e.g., 2 oz/gal sodium cyanide + 1 oz/gall sodium hydroxide. 2-5 mins.
3. Hydrochloric acid dip. approx. 1 min.
4. Repeat the previous two steps again and again until the surface is easily wetted by water.
(1 oz/gal = 7.5 gms/l)

Nick Clatworthy

2006

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The problem with nickel that has been used for overplating onto is that it usually contains additives to make it bright. This plays havoc with any subsequent nickel plating adhesion. I would suggest etching the nickel in either a proprietary nickel stripper, cyanide or even using a sulfuric acid/ hydrogen peroxide mix and then using a woods nickel followed by bright nickel.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2006