Homebrew PCBs

A short PS to my last poat. When I started using this etchant in May
2003 the SG was 1.245; as noted last post it is now 1.262.

Gramt

--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@y...>
wrote:
> Anyone here etch with CuCl2 but only rely on air for regeneration ?
Just 
> wondering what other peoples experiences are with this etchant.
> 
> I'm using HCl + CuCl2 at S.G = 1.36 and etch speed appears to be about 
> 70% of fresh FeCl3 (S.G 1.4) at room temperature. The HCl concentration 
> I'm running at is approximately 1N (or 40g/l HCl or 1 Moles/liter or 
> 4%). I found S.G of CuCl2 dramatically effects etch speed. e.g CuCl2 at 
> S.G of 1.15 was about 10 times slower etch speed than at S.G of 1.35.
> Commercially, CuCl2 etchant operates between S.G 1.35 ~ 1.45.
> 
> Adam