I use 3% (drug store strength). Start with two parts of that, add one part 37% HCl. You don't need the stronger stuff.
Message
Re: [Homebrew_PCBs] Hydrogen peroxide mixing
2011-03-06 by DJ Delorie
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Message
2011-03-06 by DJ Delorie
I use 3% (drug store strength). Start with two parts of that, add one part 37% HCl. You don't need the stronger stuff.