If you want to experiment with different strenghts of Hydrogen Peroxide, here's a list of where to find Hydrochloric Acid and Hydrogen Peroxide in US stores.
Available at Hardware, Building Supply, and Pool Supply stores
Hydrochloric Acid / Muriatic Acid 31%
Available at Grocery stores, Pharmacies
3% Hydrogen Peroxide
Available at Beauty Supply stores
Developer 10 volume or V10 = 3% Hydrogen Peroxide
Developer 20 volume or V20 = 6% Hydrogen Peroxide
Developer 30 volume or V30 = 9% Hydrogen Peroxide
Developer 40 volume or V40 = 12% Hydrogen Peroxide
Available at Pool / Spa supply stores
Baquacil Oxidizer = 27% Hydrogen Peroxide
--- In Homebrew_PCBs@yahoogroups.com, "txtom2" <unknown2@...> wrote:
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> I just mixed up some Muriatic Acid and Hydrogen Peroxide (1:2) and tried etching a very small piece of PC board (cleaned and with no mask)to see how long it takes to etch thru (room temp about 75 degrees F). I saw a change in surface color in a couple of minutes, but no etch thru after 15 minutes. I changed the ratio to 2:2 to increase the acid content and after 15 minutes, no further apparent progress.
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> Can someone please tell me what I'm doing wrong ? About how long should it take to etch ??
>
> Thanks, Tom
>