--- In
Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@...> wrote:
>
> On 26/11/2011 18:00, DaveC wrote:
> > >...
> > >HCl/H2O2 is very fast anyway, but it could probably be useful for CuCl2.
> > >
> > >Leon
> >
> > -=-=-=-
> >
> > I found it not so fast. I etched a 5" x 10" 1-sided board (consisting
> > of several duplicate small circuits) and it took almost an hour. I
> > started with a fresh batch, just enough etchant to cover the board
> > but added more as time dragged on.
> >
> > Maybe my mix is wrong? I'm using 15 percent hcl (muriatic acid) and 3
> > percent h2o2 at a mix of 1:1.
> >
> > What mix are you using?
>
> It was a long time ago, I can't remember. IT would have been 30% HCl,
> because that is what I have available. It only took about 30 seconds,
> though.
>
> Leon
> --
> Leon Heller
> G1HSM
>
Could be 15% HCl is too low, and maybe you should have a 1:2 ratio
My HCl says "383g/litre" - would that mean 38%?