I actually found my unopened bottle of Ferric Chloride from Radio Shack yesterday. So if I am unhappy with my other method I am using I can try the sponge trick.

Thanks

On 3/5/2019 3:49 AM, Fast Eddie wrote:

It's been awhile, but what I learned from using the acid-H2O2 mix is that time is of the essence...the longer the board sits in the etchant, the more the etchant starts eating away at the unprotected sides of the copper traces that you are trying to preserve, so if you have very narrow traces closely spaced they can end up being thinner than desired. Eventually I changed my technique from using the acid-H2O2 bath to using about a teaspoon or two of ferric chloride and a small piece of a car wash sponge and scrubbing the board to etch it. I found that I could etch a board in less time with less circuit trace erosion as well as focus the etching on those slower to etch areas. I used very little ferric chloride in the process so i had next to nothing to dispose of as well. Of course, there are pluses and minuses in every method you use, but this one worked the best for me. I used to get the FeCl3 from Radio Shack it was that long ago. If you aren't happy with your results you might think about giving that method a try...like I say, it worked well for me.