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Subject: Re: [Homebrew_PCBs] Re: ferric chloride question

From: toddroberts2001@...
Date: 2013-02-13

In a message dated 2/13/2013 1:54:36 A.M. Eastern Standard Time,
scubadogct@... writes:

Does the addition of Hydrochloric acid help to maintain its working
strength also?

From what I have read adding Hydrochloric Acid (muriatic acid)
does help to rejuvenate the Ferric Chloride. Here is a short
article on the subject :

http://users.monash.edu.au/~ralphk/etching-pcb.html

The article says you can rejuvenate Ferric Chloride by adding a
small wad of steel wool, then filter out the solution and add some
Hydrochloric Acid. The steel wool precipitates the copper
out of the solution. It doesn't say how much steel wool to add
or how much Hydrochloric Acid to add so you will
probably need to do it by trial and error, but should be worth a try.

73 Todd WD4NGG