Try Beauty supply stores, it is often used as a hair bleaching
solution, I recently purchased some 40% hydrogen peroxide for my
etchant.
--- In Homebrew_PCBs@yahoogroups.com, Harvey White <madyn@...> wrote:
>
> On Thu, 22 May 2008 19:08:29 +0100, you wrote:
>
> >Hello Group,
> >
> >I've been following this discussion with interest and would like
to move away from etching pcb's with ferric chloride.
> >I live in the UK and wonder if anyone knows of a supplier of the
muriatic acid and hydrogen peroxide to home users. My local chemist
was no help at all and didn't have a clue.
>
> Home supply stores often have muriatic acid (HCl) for pool cleaning
> supplies. However, the last time I was in the UK, I noticed a
> suspicious lack of such things. You might find it used for cleaning
> concrete or bricks, though.
>
> If you have a Walmart or equivalent, you might find hydrogen
peroxide
> sold in largish quantities as a disinfectant. It is also possibly
> available from beauty supply stores in a higher concentration.
>
>
> Harvey
>
>
> >Any help greatly appreciated!
> >
> >Steve
> > ----- Original Message -----
> > From: Michel Baguet
> > To: Homebrew_PCBs@yahoogroups.com
> > Sent: Tuesday, May 20, 2008 5:05 PM
> > Subject: Re: [Homebrew_PCBs] H2O2 + muriatic acid etchant?
> >
> >
> > I'm using HCl for a years. 700cc of distilled water, 270cc of
HCl highly concentrate (you can see smoke when the bottle is open)
and 30cc of H202 at 30% concentration.
> > The only problem with this etchant is that H2O2 decompose with
heat and light and if you etch another board a few days later, you
don't know what part of H2O2 is still in solution. So I put the board
to etch in the tank and take it out to see the color of the copper.
If there is still enough H2O2, it must turn brown immediately.
> > If not, I add 10cc and son on but never more than 30cc
(obvious !).
> > But the cost of HCl, H2O and H2O2 is so cheap that I often
replace the etchant, to always get accurate results with small
traces. A 200cm² double sided board with 35µ copper take between 4 to
6 min. in bubble etch tank @ 45°C.
> >
> > clintonlcorbin <clcorbin@...> wrote: Folks,
> >
> > First, I want to say "Hi". I just recently started making my own
> > single and two sided PCBs and even more recently joined the
group.
> > There is a lot of great info here!
> >
> > The question I have regards the etchant I have been using: 1 part
> > muriatic acid and 2 parts H2O2 (hydrogen peroxide). I found the
> > formula on a web page about (what else) DIY PCBs. As I was
wanting to
> > try making my own PCBs and the materials were easy to obtain and
low
> > cost, I decided to give it a try.
> >
> > All in all, I have been quite happy with the results so far. I
> > haven't tried any real fine line etching yet and the smallest SMD
> > devices are 0603, so they are pretty big. The etchant is clear,
so it
> > is very easy to keep your eye on the board during the etching
process.
> > Plus, I have been doing all my etching at room temperature with
no
> > heating at all. It generally takes about three minutes to fully
etch
> > the small (2x3" are the largest so far) boards I am working with.
> >
> > So the questions are:
> >
> > 1) How does this etchant compare to more traditional etchants?
> > 2) Does it have over etch / under etch issues with finer lines?
> > 3) Anything else I should be aware of?
> > 4) Anyone else used this etchant along with the others that can
give
> > a pros/cons?
> >
> > Thanks for the help and all the info in this group.
> >
> > Clint
> >
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> >
> >
> >-------------------------------------------------------------------
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> >
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Date: 19/05/2008 17:04
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>