Little Used EN Bath

Q: We are a job shop that offers electroless nickel plating as well as other plating processes. The EN solution is not used very often. We find that after a long period of non-use a scum-like material forms on the surface. Do you have any suggestions and how this can be prevented? G. G.

 

A: You do not mention whether you store the EN solution in a covered tank or an open tank. If you are storing the solution in an open tank, it is very possible that evaporation has reduced volume of the solution to such a level that some of the components are now forming this scum on the surface.

Storing electroless nickel solutions in a tank is not the best way. I would suggest that you store the solution in plastic containers that are opaque to minimize the effect of light on the solution. The containers should be filled as full as possible but should not be sealed since it is possible that pressure will build up in the containers over time. The containers should be stored in a cool location.

I have always been of the opinion that if you are using your electroless nickel plating baths infrequently, you are better off outsourcing the jobs to a local shop that specializes in EN. You should consider doing so.