etching pcbs

[mistercooper]

I use muriatic acid (mostly hydrochloric) mixed with hydrogen peroxide.  Works beautifully with little to no agitation in a matter of minutes.

[MR COFFEE]

I think the whole deal here is in how LONG is realistic to expect for etchant to etch 1 oz or thicker copper.

"minutes" is a vague term, eh? And what concentration?

[RaceDriver205]

I use muriatic acid (mostly hydrochloric) mixed with hydrogen peroxide.  Works beautifully with little to no agitation in a matter of minutes.

Dude! That sounds nasty!
Are you sure you dont want to try super-concentrated sulphuric acid?

[mistercooper]

lol... shrugs all around.  its just regular muriatic acid that you can get from lowes for $4 (application is burning crap off of your driveway i believe ).  The hydrogen peroxide is regular 3% concentration from any supermarket used to treat burns, cuts, etc.  Heres a nice technical explanation:

http://www.pacificsun.ca/~robert/pcb/cucl.htm

im really surprised this isnt what everyone does.  cheap, easy, regenerateable.

simply add more hydrogen peroxide to start the reaction up again.  solution turns a nice green then blue as the copper disolves into it.  for me, max etch time is around 10 minutes with gentle agitation.

[Paul Perry (Frostwave)]

Thanks for the link, mistercooper! using cranberry juice instead of universal indicator strips is just so totally DIY