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Subject: Re: [Homebrew_PCBs] Re: calcium carbonate

From: "Todd F. Carney / K7TFC" <k7tfc@...>
Date: 2013-03-18

Google "hf acid." The very first item on the page--big as life--will answer
your question and tell you all about it. Oh, I'm not a chemist, either. I'm
just a guy of normal intelligence who knows how to use a web browser. I
also know better than to broadcast my stupidity for intelligent people to
see.

Sorry about this peevish (look that up, too) response, but this kind of
"Okay, ∗Einstein∗, what does that big fancy word mean, anyway?" attitude
really bugs me. I actually think it's mostly trolls who do this kind of
thing, so it's just one more thing to ignore.

I must be in a "mood." I guess I better go solder something together.

73,

Todd
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K7TFC / Medford, Oregon, USA / CN82ni / UTC-8
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QRP (CW & SSB) / EmComm / SOTA / Homebrew / Design


On Mon, Mar 18, 2013 at 2:39 PM, AlienRelics <alienrelics@...> wrote:

> ∗∗
>
>
> OK, so keepitsimplestupid hijack's Ricks thread, and smilingcat hijacks
> keepitsimplestupid's hijacked thread. Interesting.
>
> For those of us who are not chemists, what is HF acid?
>
> Steve Greenfield AE7HD
>
> --- In Homebrew_PCBs@yahoogroups.com, "smilingcat90254" <smilingcat@...>
> wrote:
> >
> > Calcium carbonate for that matter most carbonate will react with even
> trace amount of hydrochloric acid remaining in your etchant. And yes it
> will foam because CO2 is being released in the reaction. So if your
> solution keeps foaming keep adding the carbonate. It will neutralize the
> acid for safe disposal.
> >
> > Reaction of Copper chloride and Calcium carbonate probably will be much
> slower than Copper chloride and sodium carbonate. But it should work. not
> 100% plus sure.
> >
> > ∗∗∗∗ HF acid ∗∗∗∗
> > I was in semiconductor manufacturing business so I'm quite aware of HF
> acid. Very dangerous stuff. No you can not store in a glass. It will etch
> glass. No you can not store in stainless steel container!!
> >
> > HF chemical burn is severe even at low concentration. It will penetrate
> bare skin and the flourine ion will interact with the calcium in your bone.
> HF will dissolve your bone under all the tissue.
> >
> > I didn't think you can buy it unless you can show you are a business or
> a researcher of some sort.
> >
>
>
>


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