Homebrew PCBs

"Stefan Trethan" <stefan_trethan@...> writes:
> If this feature is very important to you just throw some scrap copper
> in and etch it away, that'll rapidly increase the density.

This is what I ended up doing - I wasn't using the HCl/H2O2 solution
often enough and had to keep evaporating off water to fit in more
H2O2, so one day I just dumped about half a pound of copper into the
bucket and let it dissolve over a couple of days.  *Then* I dumped in
some H2O2 to "charge" it (it turned from brown to green) and it's been
stable since then.

At this point, my solution is so dark green that you can't see the pcb
when you're etching it.  Etching takes about 5-6 minutes, plenty fast
enough for me.

I calculated the ratio at about 1 lb copper to 3 l solution.