Dull green is ok, only when it becomes brown is the problem. If you
dilute a bit of it and it turns bright green then its pretty much
regenerated. But, this doesn't necessarily mean it'll etch ok.
I here a lot of people on this group that cannot get air re-generated
cupric chloride to work, simply because they run their solutions too
damn week. I have done a side by side comparison with fresh full
strength ferric chloride (sp.gr 1.47), under exact same conditions and
the cupric chloride (without any H2O2, ever) is only fractionally slower
(7.5 minutes for FeCl and 9 minutes for CuCl for bubble etching, 35um
thick copper at 15°C).
Adam
Phil wrote:
> I may not have all the specifics right - it was about 6 months ago but
> I did add 50 mL of 30% HCl and then aerated. It stayed a dull green,
> even after a week of aerating. 50 mL of 35% H2O2 brightened it to
> emerald green and I was able to etch a board with it. Total volume
> was 2L + 100 mL. I'm sure I was doing something wrong but I just
> wanted to etch boards not fiddle f∗rt around with chemicals.
>
> I love AP. Its clear, clean, fast, reliable and very easy to use.
> Never had to fuss with it. It just works.
>
> I still have 2.1 L of mystery etchant if some one wants it... heh heh heh
>
> --- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@y...>
> wrote:
>
>>Are you sure you added enough acid ∗before∗ aerating ? How do you know
>>what the acid concentration was after aerating ?
>>
>>I find it hard to believe it wouldn't oxidize in that time.
>>I assume you are looking for the transparent green color to
>
> determine if
>
>>the bath regeneration was completed.
>>
>>Adam
>>
>>Phil wrote:
>>
>>>I tried to use CuCl over a period of 4 months. I was never able to
>>>regenerate it using a bubbler - even left it running for a week once.
>>> I added more acid but no regen. However, adding H2O2 made a huge
>>>difference. My bubbles were fairly small so I think I was getting O2
>>>into it. I suspect there is more to it than just pumping oxygen into
>>>the solution.
>>>
>>>--- In Homebrew_PCBs@yahoogroups.com, "stan4312" <stanman@t...> wrote:
>>>
>>>
>>>>I'm attempting to bootstrap my first batch of CuCl as I type, so
>>>>this page is fresh off my bookmarks:
>>>>http://pacificsun.ca/~robert/pcb/cucl.htm Pretty good
>>>>page on CuCl. Lots of precision chemistry.
>>>>
>>>>I thought he also had the following seat-of-the-pants advice: if it
>>>>hasn't regenerated overnight, add more acid, but glancing back, I
>>>>see it must have been from somewhere else.
>>>>
>>>>Stan
>>>>
>>>>--- In Homebrew_PCBs@yahoogroups.com, "johnwhitneyfiat"
>>>><johnwhitneyfiat@y...> wrote:
>>>>
>>>>
>>>>>I have been off the group for a while and I'm sure this was
>>>>
>>>>covered.
>>>>
>>>>
>>>>>In the direction for making etchant from Hydrogen Peroxide and
>>>>
>>>>Muratic
>>>>
>>>>
>>>>>Acid, it says that you can regenerate with a bubbler. How long
>>>>
>>>>does
>>>>
>>>>
>>>>>this take? I know it will depend on the amount and the area that
>>>>
>>>>was
>>>>
>>>>
>>>>>etched, but is there a rule of thumb to make it work. I do have to
>>>>
>>>>day
>>>>
>>>>
>>>>>that I make a small bathch and it worked great on a sample board.
>>>>>
>>>>>John Whitney
>>>>>Wis X 1/9
>>>
>>>
>>>
>>>
>>>
>>>
>>>Be sure to visit the group home and check for new Links, Files,
>
> and Photos:
>
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>>>
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>>>http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
>>>Yahoo! Groups Links
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>
>
>
>
>
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBs
>
> If Files or Photos are running short of space, post them here:
> http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
> Yahoo! Groups Links
>
>
>
>
>
>
>