On 06/13/2010 02:35 PM, Frank P wrote:
> Donald,
> Please see my responses below...
>
>
>> Most any hardware store should carry it. Big box stores need to deal in large volumes to keep the margins up -- try a local hardware.
>>
> I called an old hardware store (now an Ace Hardware) in my area and they told me they carry muriatic acid in one quart containers! Thanks.
>
>
>> I'm not sure what you want the NaOH for. You can use that to neutralise FeCl when you want to dispose of it, but for CuCl, all you need is H2O2 (hydrogen peroxide) from the druggist (3%) or beauty supply (12%) is better.
>>
> The muriatic acid/H2O2 solution is used for etching, is it not?
> If you can "re-charge" the etching solution by adding H2O2 whenever you get ready to etch a board (I think someone else said this), I guess you may not need the NaOH (Drano) to neutralize the solution for a while.
>
> Of course, that raises the question, when should I be disposing of my etching solution? How do I know it is "spent" and is no longer useful?
>
Wondering that myself. I suppose the easy answer is "when it stops
etching to your expectatins". Also is probably a reason bubbling air is
better than H2O2, but bubbling creates corrosive aerosols.
> For storage, I believe a glass bottle is best (taking great care in protecting the metal cap).
>
It depends on your metric. Glass breaks easier than plastic. There is
nothing intrinsically wrong with plastic. There are reasons the stuff
is distributed in plastic bottles. Anything should be better than a
metal cap.
> Unless things change, it looks like I'm going to be using muriatic acid/H2O2 as an etching solution. Although, the 1:1 ratio stated by Mark seems a bit strong. I have to check on this....
>
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>
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