Why does my Brass get gunky after Tumbling??

[-Mischief]

When I tumble with dry media and some polish, they shine up a little bit ...BUT... When I use the thumbler with stainless media, they dull to a drab green color. How do I get them back to nice, shiny brass???

[Nueces]

I would first clean your SS pins by tumbling them in Simple Green or soap, such as Dawn, and LemiShine. Use bottled water if your faucet water is nasty. Best not to use hot water. My softened well water is too saline to drink, even after treatment, but it works well in my Thumler B with SS pins. See: http://www.stainlesstumblingmedia.com/tips/

[Smoke4320]

1 steel case will cause that issue .. Ask me how I know :)
as stated above wash pins REAL good . Cycle pins only ..several times in tumbler with dawn, rinse and repeat
use lemonshine and dawn to tumble the brass

[-Mischief]

I'll work on getting the pins nice and clean tonight. I'm certain they were all brass. I processed all of them on my Lyman case prep center.

[Nueces]

Another way to deal with problem brass (such as the black powder cases I cleaned for a friend, that looked like they had been in the sludge of a septic tank for a decade) is to soak in dawn and lemishine overnight before tumbling. Rinse well before putting them in the Thumler.

[Mytmousemalibu]

Agreed on all that has been mentioned thus far. What works good for me anyways is maybe 1/2 a tsp worth of Lemi-Shine 500-1000pcs of 9mm or less for less. Too much Lemi will cause tarnish. I use warm water and about a teaspoon of Meguiars Wash & Wax for the soap. I think it does a good job of keeping the tarnish away after they are all dry and maybe a bit slicker through the Dillon. Elevated drying temp's tend to darken the brass too. My main priority is just that my brass is clean and carbon free, shine is a nice bonus. I generally only tumble about 30min as that is enough to get the brass 99.99% clean and to minimize unnecessary peening of my brass.

[RP]

I had to much lube on some cases I ran in my SS media and it caused my brass to be coated in in gunk. I dropped them back in clean water and pins with some of laundry soap that cut the gunk and all was well again.

[Handloader109]

The citrus or lecithin isn't necessary to make the brass shine. The dawn dishwasher soap is the key. I've used just that and They shine just the as well. Cheaper detergent isn't as good.

[RP]

I use the dawn dishwasher soap and critic acid when I tumble but it just would not get the gunk out the laundry soap did. As far as not needing the critic if you run it long enough it will shine that just speeds it up and for tarnished cases it works wonders in a short timed run. And if you want you can use spent primers on cases with large mouths like 44 45s and 9 they wont get hung in but will tend to stick back in a few of the pockets. From what I understand the critic speeds the cleaning removing tarnish faster and the dawn removes the oil or lube.
When I anneal brass for swaging I heat the entire case red hot which makes them all for the most part brown. So I took a bucket filled with water and some critic acid the canning type and dumped the annealed cases right out of the fire while they were still glowing. They will turn back yellow as soon as they hit the water for the most part. Is it because of the rapid cooling or the critic acid mixed in I can not say I have not tried it with just water.

[JimB..]

When I anneal brass for swaging I heat the entire case red hot which makes them all for the most part brown. So I took a bucket filled with water and some critic acid the canning type and dumped the annealed cases right out of the fire while they were still glowing. They will turn back yellow as soon as they hit the water for the most part. Is it because of the rapid cooling or the critic acid mixed in I can not say I have not tried it with just water.

@RP
When you air dry them the outside is oxidized, so brown all over, but brass hardens when it cools slowly so doubly not what you want. When you water quench them less oxidation, and softer brass.

[L Erie Caster]

When I anneal brass for swaging I heat the entire case red hot which makes them all for the most part brown. So I took a bucket filled with water and some critic acid the canning type and dumped the annealed cases right out of the fire while they were still glowing. They will turn back yellow as soon as they hit the water for the most part. Is it because of the rapid cooling or the critic acid mixed in I can not say I have not tried it with just water.
　
If you quench (rapidly cool) the brass you are hardening it not annealing (softening) it.

[runfiverun]

brass work hardens, you can't quench it like steel.
air or water cooling makes no difference.

[Nueces]

I disagree with you guys about the effects of quenching, fast or slow, on hot brass. Brass is hardened only by working it. Heating it above the critical temperature accomplishes the annealing. The cooling process has no effect on hardness. Brass is not like steel in that regard. There are more or less technical discussions all over the net.

[JimB..]

I disagree with you guys about the effects of quenching, fast or slow, on hot brass. Brass is hardened only by working it. Heating it above the critical temperature accomplishes the annealing. The cooling process has no effect on hardness. Brass is not like steel in that regard. There are more or less technical discussions all over the net.

So much for "what I've always been told." You're right, for the brass we use the cooling makes no difference.

[725]

My brass comes clean as can be with a vinegar, hot water, dish soap & some salt bath. Agitate and rinse several times. Might do the same for your pins.

[SODAPOPMG]

if you are tumbling lubed cases their is two things that will help this problem
the first is not to tumble them too long as this homogenizes the oil and water and then it sticks to the cases (green slime) so less tumbling time will help out
second for a large tumbler is to add about 1/3 cup of flour, general purpose self, rising, whatever, doesn't mater but it is something for the oil to bond too and stay off the cases

[marlinman93]

When I tumble with dry media and some polish, they shine up a little bit ...BUT... When I use the thumbler with stainless media, they dull to a drab green color. How do I get them back to nice, shiny brass???

How much liquid (water/soap mix) are you putting in with the pins and brass? If it's not wet enough, it could be part of the problem.

[gwpercle]

To me , the water and wet tumbling got them clean but afterwards the brass darkened. Went back to dry treated walnut to get the bright as new shine. Also the polished cases stayed bright .
Gary