Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Andres Hernandez <afhernandez79@...> writes:

> Intersting etching chemicals.... can you tell me what is the
> proportion between Muriatic Acid and Hydrogen Peroxide.

It depends on the grade of peroxide. If you're using common 3%
drugstore grade, it's "add one part acid to two parts peroxide". For
stronger peroxide grades, you have to dilute the peroxide first.

Note that the HCl+H2O2 etchant turns into CuCl etchant with use, so no
need to discard it. See:

http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/
http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/