Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Morris Odell" <vilgotch@...> wrote:
>
> Hi all,
> 
> I've been using FeCl3 for longer than I can remember but the solid
>form is 
> getting hard to find these days. I'm looking at alternatives such
>as CuCl2. 
> Most of the procedure looks pretty straightforward.
> 
> What concentration of H2O2 did you use? Was it the commonly
>available "10 
> volume" from the pharmacy or do you need something stronger?
>

H2O2 is available at beauty supply stores in 20, 30, and 40 volume for
bleaching hair. Depending on the store, you may or may not need to
have a licensed cosmetologist buy it for you. (Sally's Beauty Supply
doesn't have a license requirement but many stores do.)

Incidentally, each 10-unit increment of 'volume' is actually a 3%
increase in percentage strength. The 10 volume is 3% H2O2, 20 volume
is 6%, 30 volume is 9%, and 40 volume is 12%. 

You also may be able to buy industrial strength at up to 35%
concentration but I'd suspect that restrictions may be in place for
buying it that strong. A 40-volume (12%) works well for CuCl etching.

http://en.wikipedia.org/wiki/Hydrogen_peroxide 


Regards, Bob