Homebrew PCBs

James,
I believe you need to introduce oxygen into the etchant (air bubbles) to increase the effectiveness of the etching process. If you look at some of the "how-to"s in the Links section of the Group, you might get some ideas.

It seems that the following affect the results:
1) air bubbles
2) temperature
3) HCl to hydrogen peroxide mix

I'm just beginning to investigate the use of CuCl, so the information I have provided is based on my research on the Links page and on the Internet.



--- In Homebrew_PCBs@yahoogroups.com, "James" <jamesrsweet@...> wrote:
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> --- In Homebrew_PCBs@yahoogroups.com, "Ben L" <bhleavi@> wrote:
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> > > I found cupric chloride to be very slow at room temp, it benefits from heating even more than FeCl. HCl + peroxide certainly works fine at room temp though, until enough of it converts.
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> > I have never heated mine before.  In fact I have it on the back porch and have etched boards fine in cold weather.  I just pump lots of air into it.  Sometimes add a little HCl if it seems to be slower than normal.  I kept it covered when not in use but can still vent.  So times will leave it uncovered to reduce it down some.  I normally don't add any peroxide.
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> > Ben
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> How long does it usually take? I found that mine took ~15 minutes to etch at room temp, while I'm used to etching in 3-4 minutes. Longer etching times cause more problems with pitting and etching under the resist. I had trouble making reliable 10 mil traces unless I heated it.
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