On 11/11/2010 01:39 PM, Philip Pemberton wrote:
>> If you want to skip right to CuCl, I found that about half a pound of
>> copper converts 3 liters of CuCl etchant.
>
> So just chuck 1lb of copper pipe into the tank, and leave it with the
> air pump running?
Well, you want enough copper to get the density to the low end of the
useful range, but not so much that you get to the high end. You want to
build the rest of the density with circuit boards :-)
but do that ∗after∗ you etch your first batch of boards. The hcl+h2o2
etchant is pretty fast at first, might as well take advantage of it.
> You mention that the peroxide degrades in about a week, am I right in
> thinking this only applies to the HCl+H2O2 etchant, i.e. by the time
> it's CuCl, this is of little effect?
I don't add more peroxide to my CuCl tank any more, but I do add more
acid occasionally (the Cl in CuCl has to come from somewhere)
> Do sealed bottles of peroxide degrade in the same way, or just open bottles?
If they're in ∗dark∗ sealed bottles, should be fine for longer. They're
cheap and easy to get though, use the 2% you can buy in supermarkets and
drug stores.