# Copper plating a non metallic material

1. Aug 16, 2016

### wolram

I want to copper plate a non metallic material I will be using genuine silver paint to coat the material, my problem is how to estimate the time it takes to deposit a layer 25 thou thick.
I have a variable voltage, amperage power supply, i guess it has some thing to do with varying the amperage
if i set the voltage at 12 volts.
The tank i have is 2ft by 1ft by1ft

2. Aug 16, 2016

### Bystander

What area? You're going to be plating out some volume of metal; current times time for copper is what?

3. Aug 16, 2016

### gleem

According to Faraday's Law of Electrolysis the charge in coulombs needed to deposit m grams of material with a valence number n and atomic mass M is

Q = 96520⋅ n⋅m/M (coulombs)

To obtain a certain thickness you need the area of the plated surface to get the mass plated. By monitoring the current flow you should be able to obtain the time it takes.

4. Aug 16, 2016

### Staff: Mentor

I haven't worked with electroplating before; how do you start the plating of a non-conducting object? It seems more straightforward after you have the initial conducting layer plated on so you can make electrical contact, but I'm not understanding how the first layer adheres to the non-conducting object. Thanks.

5. Aug 17, 2016

### Kevin McHugh

In extrusion coating, i.e. polymer coated paper, the substrate is ionized by corona treatment. This gives the coating a charged surface for the polymer in which to adhere. I imagine a similar process is used for metallized coating on plastic. Mylar is commonly metallized.

6. Aug 20, 2016

### Tom.G

7. Aug 20, 2016

### Chronos

Electroplating is accomplished by placing the cathode behind the non conductive surface. Electroplate time depends on the spacing between the cathode and deposition surface and current density.