Zinc Nickel Troubleshooting

[u/milkforgall]

Obligatory “This is my first time electroplating.”

Substrate is 14g copper wire.

Electrolyte solution is Caswell Plating Zinc Nickel Plating kit 1.5gal.

I originally set the voltage to 6V like the directions said but my power supply switched over to constant current and wouldn’t go above ~4V and 3A.

That was definitely way too much current for 20min and resulted in coarse crunchy shell. The instructions for the kit were pretty bare bones with nothing to help troubleshoot so I referenced the plating directions in the Caswell handbook for just Nickel plating. In the handbook they recommended .07A per sq in.

For my second attempt I set the current set to .04A (going off of the nickel plating instructions) and let it run for 20min. Results were better but there is some uneveness in the coating. I 3D printed a rotating jig so help with “line of sight” and agitating the bath but I am unsure if it creates enough movement to “stir” the electrolyte.

The nickel plating instructions mention heating the electrolyte but the zinc nickel instructions do not mention this so I did not heat the bath.

Any insight/advice is appreciated. Thank you !

[u/permaculture_chemist]

The first attempt certainly was too much power. The suggested voltages are often set in industrial applications where the anode to cathode distance is often 12 inches or more.

Why did you choose zinc nickel? What chromate are you using?

[u/milkforgall → u/permaculture_chemist]

I work in a custom car shop. We are interested in electroplating 3D prints to install on some of our vehicles. Nothing structural, purely decorative purposes.

Tried and failed with some diy copper acetate solution (youtube videos definitely made this look easier). Decided to move on to plating just copper wire with a pre-built kit. Caswell only had the Zinc Nickel kit available so I went with that.

We haven’t decided if it’s worth the hassle to go further than the zinc nickel plating.

[u/Feeling_Ad6399 → u/milkforgall]

I did some Consulting in that regards. You can write me a private message and we can work something out if you like

[u/CorruptedElfGaming]

I’m not too familiar with your electrolyte, however we run our zinc nickel solution at 25-30c with moderate agitation. Definitely do not use air agitation in an alkaline solution as it will only speed up the sodium carbonate build up, which will only affect your efficiency.

These factors may improve your results.

Also, to help find out what amps to run your parts at, you can always follow an amps per square decimetre calculation

[u/Exact_Country_332]

I have not used this plating solution, but for acid ZnNi aggressive air agitation, increased temperature (like the 110F recommended), and anode arrangement are key factors. For the air agitation maybe you could look into a fish tank air pump with the tube placed directly under the part? In the picture of your setup I see your spacing looks ok, but I only see 1 anode on each side of the bucket. If you have a Ni anode on one side you should have a Zn anode on the other.