The Wayback Machine has one: http://web.archive.org/web/20100206170229/http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html
--- On Tue, 5/8/12, Aaron <ataylor@...> wrote:
From: Aaron <ataylor@...>
Subject: [Homebrew_PCBs] Re: Long-Term CuCl2 setup
To: Homebrew_PCBs@yahoogroups.com
Date: Tuesday, May 8, 2012, 3:25 PM
> Whether the copper is oxidized to Cu^+2 can be determined
> by color. I just bubble air until all traces of brown/mud
> are gone as per Seychell's instructions.
He had a great web page describing the process but it seems to be down. Does anyone have an archived copy of the page?
http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/index.html
It covered how to determine optimum pH, specific gravity, temperature, etc and was probably the most thorough coverage I have seen given to the topic.
Aaron
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