On 08/05/12 23:39, poofjunior wrote:
> Hi everyone,
>
> I noticed that a few people have mentioned regenerating a cupric chloride
> etching solution with a few options: aerating it with a fish pump, adding
> Hydrogen Peroxide, or even using some form of electrolysis.
>
> Has anyone had any long-term success with this process? How long does it
> take to aerate? Is there any excess waste that needs to be dumped
> eventually?
No.
> Are there any circuits I can create to duplicate an electrolysis setup?
>
> I'd greatly appreciate more details on anyone's success or any insights on
> maintaining a CuCl2 solution for use over and over again. If I can duplicate
> a setup, or make my own, I'd be happy to write up a tutorial.
Ferric chloride is commonly known as Profloc-F for floculating in sewer treatment.
You shouldn't dispose of ferric chloride if using air agitation such as
bubbling, because it'll eventually turn green and work as copper-chloride etcher
and last forever (the oxygenation is needed iirc). My etchant is years old and
still working well.
I use a bubble etcher same as the first in this list:
http://www.esr.co.uk/electronics/pcb-tanks.htmThe only aeration that's needed happens during etching anyway.
That one comes with a heater, but i get a complete etch of double-side pcb at
room temperature in ~12mins.
Just keep the stuff topped up with hydrochloric acid every few months and it'll
work well instead of the water evaporating out. Keep a cover over the container
when not in use.
When starting with new ferric chloride, first dilute it 1:1 with water, then put
a bit (like half a cup per litre) of hydrochloric acid in it.
Copper saturated etchant is excellent weed killer. Apply only selectively, or
you'll end up with a large black spot on the lawn.