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Subject: Re: [Homebrew_PCBs] Ferric chloride dilution

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-11-04

On Fri, 04 Nov 2005 11:03:45 +0100, Mike Young <mikewhy@...>
wrote:

> I'm having a tough time finding ferric chloride. Pretty tough to imagine
> in
> a large metro area (Chicago), but TV retailers is all I find under
> Electronics in the yellow pages. If I buy bulk anhydrous, what dilution
> should I make the working solution? I saw 40% by weight on MG's website
> and
> other places. (What, exactly, is a Baume? as in: "To form the basic stock
> etching solution, water is added in the ratio 2 parts water to 1 part
> ferric
> chloride solution in a solution strength of 42° Baume.")
> (http://www.polymetaal.nl/beguin/mapf/ferric_chloride.htm).

Well, you are looking in the wrong place! Look for chemicals not
electronics.

I dunno about the dilution, i mixed it according to package (mine came
from a electronics mail-order).

Baume is some nasty scale for concentration i think, dunno why one would
prefer it over %, ever.

ST