Homebrew PCBs

Oxalic acid removes ferric chloride stains. I've got a big bottle of it somewhere but have never used it.
Leon 

    On Monday, 3 July 2017, 2:56, "'Brad' unclefalter@... [Homebrew_PCBs]" <Homebrew_PCBs@yahoogroups.com> wrote:
 

     I have been using ferric to etch boards for a while now.  Recently I got lucky and came into a cache of 1973 vintage copper clad PCB stock, which will enable me to make some reproduction pieces that are pretty much indistinguishable from originals in terms of look.  However, I have noticed that the ferric solution stains these boards, adding a yellowish tint.  Is there any way to avoid this?  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