Copper colored brass after wash???

[LeftyTSGC]

Can someone please help me understand why a load of brass that I tumbled turned out copper colored? I have attached pictures.

I have washed thousands of pieces of brass. my recipe is dawn dish soap, lemi-shine and water. Wet tumble for 2-3 hours.

You can see the difference between two sets of washed brass and a closeup of the dis-colored brass. It actually looks like the brass is copper.

LeftTSGC

 

[JimKirk]

May have got the Lemi-shine a little strong ....

 

[splattergun]

Maybe too much acid (lemishine), Lefty. It leeches the tin from the brass, leaving copper. When I wash brass I use just a little lemon juice and a dash of salt with the Dawn, and soak for no more than an hour, with a few shakes through the process. Double rinse in very hot water, then dry in the oven on its lowest setting.
Happy brass.

 

[LeftyTSGC]

I guess I could of use too much lemi-shine, I am normally careful to just put a touch in. I have never had this happen, have cleaned thousands of brass over the past two years.

Is this brass (copper) still usable? or do I toss it??

Lefty TSGC

 

[50 Shooter]

Should be okay but I would be careful with the lemi shine.

 

[CMV]

I have plenty that I 'pinked' with the initial runs of the ultrasonic that were just fine. Tumbling in walnut takes them back to same brass color as everything else. They are still in my mix of plinking brass & doing fine. It's not a hot load but they seem no worse after being 'pinked'.

For me, Speer brass is the 'acid test'. Those turned pink faster or to a greater degree than any other HS if the LemiShine is too much.

 

[joneb]

It leeches the tin from the brass

I thought brass is mostly a alloy of copper and zinc, and bronze is a alloy of copper and tin.

 

[rcmodel]

Cartridge brass = 70% copper and 30% zinc.

No tin in it.

If you are leeching the zinc out with acid wash, it will become harder & more brittle.

IMO: that's why tumbling is my preferred method of cleaning brass.
You can't hurt it.

rc

 

[blarby]

Please check all of that batch for :

Steel cases

Any other source of ferrous metal.

ReplY.

Even if not, acid in sufficient strength combined with copper and zinc produces a galvanic reaction.

What you are seeing is brass robbed of zinc from the surface In that reaction.

If you continue to add lemishine to that same batch of media, this will happen much more rapidly As the PH level continues to grow. Make sure and wash your pins well.

Since you are wet tumbling I presume, you made a nice low voltage battery Out of each of your cases, and thrEw the zinc out with the bath water.


Of note... This is why those of us who wet cleaned in ultrasonic before pin tumbling became popular, Used a baking soda wash to neutralize remaining surface acids. Until your brass is bone dry, this reaction is still occurring.

Ya science.

 

[splattergun]

I thought brass is mostly a alloy of copper and zinc, and bronze is a alloy of copper and tin.

I stand corrected

 

[50 Shooter]

If the brass turned pink you're definitely leaching the zinc out and as RC stated, making it harder and brittle. Whatever you're using I would stop and rethink what you're using, last thing you need is a failure in your face!

 

[Toprudder]

I had that happen once. Less Lemishine, and wash/rinse with cold water. I also have not had the problem at all since I switched from using Dawn to using Armor All Wash-n-wax.

 

[50 Shooter]

I should have added that if you want to use a liquid cleaner, try Iosso! Fastest stuff I have ever used and it'll clean surplus brass in minutes not hours. Nothing else cleans surplus 50 BMG brass as fast as Iosso and if you want it looking factory fresh, run it in corn cob media for about an hour.

You'll need to dry it off in the oven set on low, summer time you can leave them out in the sun for a bit.