copper sulfate destroys my plated parts

[emosms]

Hi, trying to refinish some chrome plated parts.

Matted the surface with scotchbrite and plated in citric acid with nickel + extra copper electrode for color.
The nickel electrolyte was home made - self saturating it with using electrolysis, no nickel sulfate/ chloride added.



But, the nut and the handle wont hold nickel or coper in that electrolyte.
Someone suggested I use copper sulfate to copper plate those parts and then finish with nickel like the knob.

But, when I put the parts in copper sulfate electrolyte, i get ulcers on the exposed base metal.
When preping the parts I over sanded (sometimes intentionally) some sharp corners to the steel/ zamac base metal to smooth the things out.




Not only I damaged the details, but still there are parts which refuse to copperplate (the nut on the top).
I tried the solution in HCL, citric acid, dilluted it, added base to higher the PH, using lower plating current, but the problem persists...
The metal from the exposed parts gets eaten away....

Can u suggest some copper plating solution, so the exposed metal is safe?
Or a pre-treatment, so I dont get ulcers?
Copper sulfate seems to be pretty aggresive.

Best Regards - Emil

[nicamarvin]

Best Regards - Emil

What are the parts made out of? If they are made out of reactive metals(like Iron, Zinc, Zamac, Aluminum) you will need to coat it first with a Cyanid Copper coat first or What Caswell sells as Flash Copper which is a proprietary formula. Then after the flash copper you can follow with Acid Copper then Nickel