Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hello, is there a way of working out the strength of ammonium
persulphate, I have been using about 5 tablespoons per litre of water,
I have the temperature as hot as the hot water cylinder will supply
and it takes about 15 minutes to etch. Are there any plans around for
a small spray etching setup or could someone point me in the right
direction for what sort of pump to use.
Regards
Philip