"05OCT2005: I've found a new home-made etchant that I really, really like. And it's very cheap,
and widely available. It's made by adding 1 part Muriatic Acid (the common kind that's sold in hardware stores,
which is actually 28% Hydrochloric Acid) to 2 parts Hydrogen Peroxide (the common 3% kind that's sold
in drugstores and pharmacies). This etchant can etch a 1-oz board in about five minutes, at room temperature,
with gentle mechanical agitation. And it's almost transparent. I mix it in a plastic tub and wear rubber
gloves so I can use a balled-up paper towel to gently wipe the surfaces of the board, as it etches,
which seems to speed up the etching time, considerably. (Caution: The concentrated acid's fumes would
be very bad to breathe, or to have around metallic items. And the acid would be very bad to get onto
anything that's not plastic.)"
My observations: The resist pattern was printed on Press-n-Peel transfer film, highly recommended.
And ironed on after the board was cleaned with Instant Copper Cleaner from revere Ware.
This etching solution will etch a board in 5 minutes, at room temp. when
the solution is constantly sprayed over it with a basting syringe.
A cup and a half of the solution etched about 12sq" with no problems.