The AM Forum

Randomly searching for other things, I found this site.
pretty interesting.http://www.gw8ljj.com/ (http://www.gw8ljj.com/)

Jez - It looks like he still uses Ferric Chloride - What a mess!

I do essentially the same thing he is doing in my garage with 10% of the junk he has - and I'd bet I get better quality.

What is your preferred soup? Ammonium Persulfate, or??

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I used ammonium persulfate for years. It etched clean and fast but required heating.

I now hydrogen peroxide,  drugstore variety 2 parts,  and muriatic acid 28% I believe from Lowes - 1 part. Usually just eyeball it - add the acid to the peroxide. I buy the peroxide from Amazon for about $14 a case and the muriatic acid from Lowes for $7 a gallon.  It is fast, cheap, clean, room temperature and I like it best. It is slightly irritating to the skin but no worse than the persulfate. The end product is copper 2 chloride which is reasonably benign.

I clean the finished product with steel wool and use Liquid Tin which works pretty well. I have also imersion silver plated and that works well also. The Liquid Tin is expensive and you can make the silver plate solution for less money (or used to be able to - I haven't priced silver nitrate in a year or so)
The tin or the silver just is just for solderability.

Ferric sulfate will corode most anything in site. It will stain also.

Pat

What's ur etch time compared to the others?

What about "refresh" for the soup? Or down the drain?

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About 3-4 minutes under agitation (rocking the tray) about the same as ammonium persulfate (hot)

Faster than ferric chloride.  Throw it out. It is supposed to be good for several times, but it is so cheap, I just throw it out. I used to keep the persulfate and re-use it at least once.


Pat