Electroplating already plated hardware

Haych

I'm going to have a go at copper plating some bits of hardware for a partscaster I intend to build.

The parts I'll be plating will already be nickel or chrome plated, probably the latter as I'm experimenting cheap to start with.

Will the copper plating adhere well enough to a chrome plated surface or would it be better to attempt stripping or dulling the chrome first?  If so what would be the best way to prepare the parts for plating with copper acetate?

TIA

Roland

You’ll need to degrease the metal, and remove also any surface coating. Abrasives will leave a scratched surface and the copper coating will ridge along the scratches. Spirit vinegar is your best choice, but don’t leave it in too long because the surface will pit.

Funkfingers

The chrome plate's connected to the nickel plate.
The nickel plate's connected to the copper plate.
The copper plate's connected to the bare metal.
Now, hear de word o' de Lord.

To get that Schaller "aged Copper" appearance, you need to remove electro-plated layers not add more.

streethawk

Chrome plate: abrade, soak in ferric chloride.
Nickel: just soak in ferric chloride.

Rinse in water. You're done.

Chrome is tricky though, be careful not to scratch the copper plate. Would recommend going with nickel.

I've got some pics of the process somewhere.

Haych

Funkfingers said:

The chrome plate's connected to the nickel plate.
The nickel plate's connected to the copper plate.
The copper plate's connected to the bare metal.
Now, hear de word o' de Lord.

To get that Schaller "aged Copper" appearance, you need to remove electro-plated layers not add more.

I did read up that copper plate is used before other plating is applied on top, since apparently it's easier to apply other plating to copper than the base metal so all of that ^ is on my radar.  That said, it'll be a bit of fun and the process of plating seems easier than de-plating, at least to me it does

I read somewhere that you can reverse the polarity of the plating process to remove existing plating but I know not whether it would work with several other finishes plated on top of the copper and one source said it would contaminate the copper acetate solution to do it in reverse.  I don't know enough about the process to know why, though.

Mainly I'm doing it for a bit of fun and hopefully I'll get some acceptable results since I'm not looking for perfection.

Roland

The copper layer under the nickel and chrome will be very thin. Thick enough as a base for electroplating, but not to take normal wear and tear. I’d replate a thicker copper layer on top.

streethawk

Roland said:

The copper layer under the nickel and chrome will be very thin. Thick enough as a base for electroplating, but not to take normal wear and tear. I’d replate a thicker copper layer on top.

Not in my experience! Thicker than the damn nickel.