Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Les Newell <lesnewell@f...> 
wrote:
> Thanks Adam,
> 
> Sounds like my solution is quite low in copper. If I had realised 
this I 
> would have used less acid and made up less etchant. I bought 250g 
of 
> copper (II) oxide and based my calcs on the information I found 
here:
> http://www.pacificsun.ca/~robert/pcb/cucl.htm
> Never mind, the copper level will build up by itself so it does not 
> really matter. This is only hobby stuff so an extra 5 minutes or so 
> makes no difference anyway.
> 
> Les
> 
> 
> >You can put more copper oxide to increase etch rate. From memory 
> >I think its around 140 g/L of copper(II) ions is good 
concentration.
> >What copper oxide did you get, the black stuff or red ?
> >Black is more common which is copper(II) oxide.
> >100 g copper(II) oxide (black) = 66g copper
> >100 g copper(I) oxide (red) = 89g copper
> >
got a question
is it attack only copper or also tin (tin as resist after patern
plating)

gr. Roel