Anybody know of a dip that will clean brass almost instantly? Or at
least in a few minutes? That is sold at the store or hardware store? I
have 400 small parts that came out of the tumbler oxidized and need to
be delivered today. This has not happened before so I don't know what
Eric R Snow
When I am cleaning rifle brass I first soak them in a 2% phosphoric acid
solution, then put them in my tumbler and they come out very bright. They
are pretty bright just from the soaking but the tumbling does a great final
polish. Don't know what other sources are available but I have been using
the Baqua Spa filter cleaner solution. First I use it to clean my hot tub
filter, then I keep the bucket of solution around to clean brass.
A phosphoric acid solution is available at most autoboby supply stores (NAPA
was a source when they carried a full paint/refinishing inventory). It's a
diluted, but fairly strong solution thats diluted further with water in
different ratios for different metals.. usually, there are some examples on
It's commonly referred to as metal prep in the trade. It's used to remove
oxides and to etch bare metals prior to applying primer.
"Eric R Snow" skrev i en meddelelse
I havent specifically used this to clean brass, but I have noticed that
nitric acid ( HNO3 ) does a pretty good job og cleaning up brass fittings
and valves.. I work in the dairy processing industry, where HNO3 is widely
used for cleaning..
Use a 2-3% solution in warm water and do this outside or in a well
ventilated area, HNO3 makes some nasty fumes.. Dump the used solution in the
sewer as it may produce some explosive byproducts..
The treehuggers are probably going to flame me for this, but dumping HNO3 in
the sewer isnt really a problem since the pH in normal sewage tends to be on
the alkaline side of 7....
We use approx 1.5 metric tonnes of concentrated HNO3 per 24 hrs just to get
the pH in our wastewater below 9 as specified by the local sewage processing
Dont forget gloves and goggles!
I've pickled brass items in warm sodium bisulfate solution (aka sparex
acid pickle) before to remove the copper oxides, but I'd like to point
out that when I did it, the parts did not come out with a bright yellow
brass shine. They emerged from the pickle with a clean but dull reddish
coating of copper which I buffed off afterwards. I'd imagine that to get
back to bright brass color after this kind of dip you would need to
tumble your parts or possibly give them a nitric acid drip just long
enough to dissolve the copper. Other home methods I've heard of include
vinegar and peroxide pickle, which may or may not have the same
When doing this one might consider the effects of concentrated
solutions on the house plumbing. Also this might not be the
best approach if one has a septic tank....
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
Thanks Brad and all you others who replied so fast. I used phosphoric
acid. I did mix up some sparex the night before and left one part
soaking in it. Absolutely no effect. I believe the oxide coating
formed during tumbling was different than what occurs from wxposure to
air over time. Soaking in phosphoric acid also had no effect. But
tumbling with phosphoric acid cleaned up the parts in about 10
"jim rozen" skrev i en meddelelse
Well... a 2-3% solution in small quantities shouldnt be a problem.. otoh..
if you want to be on the safe side dump it in a public sewer :-).. Or
neutralise it with sodium hydroxide and dump it in whatever sewage you may
Another dairy facility in the area had a "small" leak from a storage tank
used for lye ( sodium hydroxide, used for cleaning ).. Ran straight into the
separate sewers for rain water and into a small stream nearby... That killed
a fish or 2 :-).. The company did pay for the cleanup tho..
Eric, if the sparex and phosphoric acid dips did not work, your "oxide"
was probably not oxidation at all, but some other kind of coating. What
color was the coating and what were the parts originally tumbled in that
caused the problem? In my experience a proper (140 deg) Sparex Acid #2
bath will effectively remove red and black copper oxides, copper
sulfate, carbonate, acetate and chloride, all of which can form on
copper alloys outdoors.