[TheForge] Making Ferric Chloride etchant

[Ron Childers]

But Bruce... after I etch a bunch of blades with ferric chloride, it gets
really nasty and after a while it quits working...It must reach a saturation
point- the blades I put in the stuff are polished shiny like chrome, so
there really isn't much stuff like iron rust to gunk it up- what is the
chemistry involved here?. (I took physics; makes more logical sense to me
than chemistry).

Ron Childers

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of Washington, Aubrey O.
Sent: Tuesday, November 21, 2006 1:52 PM
To: Sponsored by ABANA
Subject: RE: [TheForge] Making Ferric Chloride etchant

So, Bruce, if I start with muriatic acid (which some people recommend) and
etch enough blades with it, eventually I will end up with ferric chloride
(which other people recommend).  Do I have this right?  Sounds like a
win-win.
 
Any reason to prefer muriatic acid over ferric chloride?
 
Aubrey

________________________________

From: theforge-bounces at mailman.qth.net on behalf of Bruce Freeman
Sent: Tue 11/21/2006 12:20 PM
To: theforge at mailman.qth.net
Subject: [TheForge] Making Ferric Chloride etchant



Buy a jug of muriatic acid.  Add scrap iron.  (Flammable, explosive
hydrogen gas will be given off, so do this outside, using a container
not tightly sealed.)  When acid will dissolve no more iron, the red
solution is Ferric Chloride.

Bruce
NJ