The whole process i will describe is based on an electrolytic bath
using a copper sulphate dilution
itself is a quite easy thing: it is a process, which enforces a chemical reaction due to electricity
. What kind of reaction is happening depends on the ingredients being used.
A detailed description of electrolysis can be found here What do i need for the setup?
- a power source ( DC, continuous current
) and electrodes
- an electrolyt ( a conductive liquid )
- copper as basis material and for th anode )
- some plastic or glas containers.The Power Source
It is a good idea to have a switchable power supply. I use one from Graupner
It can adjust both current and voltage, so i can vary a bit depending on what materials i use.
I would aim at having at least 12V and 15-20A output.The electrolyt
A traditional substance for eletric etching of copper and zinc seems to be copper sulfate.
It easily dissolves in water to a nice blue liquid. I used a concentration of 4 parts water to 1 part copper sulfate ( assuming 1 kilo being one litre ;) ). Copper sulfate is defined as an irritant, but can be bought online. The potential danger is that it destroys organisms over a longer period of contact. Don't put it on your skin and do not drain it in the sink.
If you need to get rid of it, contact your local waste disposal dealer.Copper
Since you want to etch copper, you need to copper object you want to etch. This will be attached to the anode of the power source to let the current run through it. On the cathode you need another piece of copper, on which the Cu2+ molecules can settle. I actually used brass, also works fine, as will all other materials, that are able to join with copper.
Written in chemical terms, this happens:
On the Anode: Cu => Cu2+ + 2e-
On the Cathode: Cu2+ + 2e- => Cu
The anode dissolves slowly, producing cations, which will transform copper at the cathode through reduction of copperions.