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Subject: Re: [Homebrew_PCBs] Re: Sponge etching with HCl and H2O2?

From: Benjamin Blumer <b3nzilla@...>
Date: 2011-11-27

I would take that to mean that with those concentrations, your solution is
already too diluted. If you don't have access to 30% HCl, I'd just use the
ratios they give (~1.25 parts H2O2 to 1 part HCl) and hope for the best.

Sent from my iPad

On 2011-11-27, at 3:40 PM, DaveC <davec2468@...> wrote:



I entered 3% h2o2 and 15% hcl into the calculator. The result is:

Mix h2o2: 66.7%; hcl: 53.3%; water: -20%

What does it mean if I get a water result of minus 20% ?

Thanks,
Dave

-=-=-=-

>Here's a web page about using the acid/peroxide etchant. About half
>way down the page is a calculator for the mix. Input your % acid and
>% peroxide and it tells you how much water you have to add.
>
>http://www.dr-lex.be/hardware/tonertransfer.html



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