On 23/03/12 02:07, sheldon_mp_cooper wrote:
> --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw<rjshaw@...> wrote:
>>
>> The deep olive colour is when to add HCl and use as a long-term etchant.
>
> But, at that point, highly dangerous chlorine gas WILL be generated from the
> reaction, as was warned about in the other link I referred to where the gent
> said he'd used the same etchant for four years.
Adding a cup of HCl to a litre of spent or unspent ferric chloride will cause
absolutely no outgassing whatsoever.