"Ed Huntress" wrote in message
...

wrote in message
...
Ok, so I am an idiot. I pushed things too far and may have cost myself
a bit of money in the process. I work with beer equipment and had some
old brass draft beer towers that needed some love. One of the cleaning
chemicals I work with is hydrochloric acid and I've noticed that when
I use this on brass parts they shine. I think this may work on the
tower I have so I soak it in a solution of 7 oz. hydrochloric acid and
4 gallons of water overnight. First day it looks good, second day it
looks better, third even better, fourth day it is pink! What happened?
Is there anything I can do to restore the shine? Any help would be
appreciated because I would like to save this thing if I can. Thanks
in advance.

If it's pink, you've de-zincified it. Hope that it's only on the surface.
If so, you may be able to abrade the surface copper off (maybe some fine
wet-dry sandpaper, followed by a couple of grades of abrasive polish) and
get back down to brass.

Or maybe you'll get really lucky and someone here will have an easier
solution. Good luck.

--
Ed Huntress

Ed's right , you have etched the zinc out of the surface.

If you are lucky and it is not too deep, you can use a hydrogen peroxide
pickle technique to strip back the copper rich surface.

http://www.artmetal.com/files/import...onfe/H2O2.html

It will leave the surface dull, but well within the range of hand polishing.
4 gal is a lot of peroxide though.

It is also a great technique for cleaning up when you burn out the zinc with
a torch after silver brazing or etching it out with acid flux.

HCl is a little strong for general cleaning. I prefer citric acid or sodium
bisulfate (AKA Sparex, or sold in the pool supply section under various
brand names as a granular ph reducer for pool water).

Paul K. Dickman