Case cleaning mishap

savagefan

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Cleaned a small batch of 06 in my ultrasonic using the lemishine/ sunlight mix as usual. Threw my greasy LEE resizing die in with the brass. No bueno. Don't do it.
 
Looks like you might have used a bit heavy dose of the Lemi shine. Ive never had what happened to you but noticed some discolouration when using too much Lemishine. I also dont use ultrasonic, just tumble with SS pins or no pins. You think the Black looking gook is from your sizing die redepositing?
 
Isn't LemiShine citric acid? If so, I'm guessing you had a galvanic (electrical) reaction between the copper/zinc in the cases and the steel die.
Where would the power (electricity) come from? I am genuinely uncertain of how such a reaction would proceed. And why would it affect only some cases and only some parts of those cases? It should occur uniformly over everything in the bath.

I ultrasonically clean parts made of different metals all the time, typically aluminum, steel, stainless steel and have never seen such an effect. Of course I use specific ultrasound liquid and don't include lemi-shine.
 
Where would the power (electricity) come from? I am genuinely uncertain of how such a reaction would proceed. And why would it affect only some cases and only some parts of those cases? It should occur uniformly over everything in the bath.

I ultrasonically clean parts made of different metals all the time, typically aluminum, steel, stainless steel and have never seen such an effect. Of course I use specific ultrasound liquid and don't include lemi-shine.

If you don't involve the citric acid component you won't get the same results.

When I get a few aluminum cases mixed in with my brass in my citric acid/soap cleaning solution it's not uncommon for the aluminum to get eaten away a bit and steel that are copper washed will turn pink.

The OP definitely had a chemical reaction going on.
 
Yep that once shiney steel die has been electroplated, the cases furthest away from the die did not discolor. I trimmed the brass later today and noticed that discoloration is just on the very surface, inside is nice and brassy. The mix in the cleaner is 1 tbsp Lemishine 1 tsp detergent on a filled bath. I won't do this again for sure but thought it would be fun to post.
 
Yep that once shiney steel die has been electroplated, the cases furthest away from the die did not discolor. I trimmed the brass later today and noticed that discoloration is just on the very surface, inside is nice and brassy. The mix in the cleaner is 1 tbsp Lemishine 1 tsp detergent on a filled bath. I won't do this again for sure but thought it would be fun to post.
Too much citric acid would be my guess, when I bought my FA wet tumbler I was reading up on what people were using for soap/citric acid mixes etc and that was one thing that usually popped up.

You don’t need much, when I clean a full load in the wet tumbler I’ll use a .40s&w case or a .45acp case of citric acid with a small amount of soap. Cases come out cleaner than new.
 
I've been using the mix quoted since I got the unit a few years ago and am very happy with it. This was the first time l threw a die in there, won't do it again for sure, yes the heater was at 60c. On second thoughts it might be a cheap way to electroplate something that needs it, I'll save my worn out brass for a future project.
 
Where would the power (electricity) come from? I am genuinely uncertain of how such a reaction would proceed. And why would it affect only some cases and only some parts of those cases? It should occur uniformly over everything in the bath.

I ultrasonically clean parts made of different metals all the time, typically aluminum, steel, stainless steel and have never seen such an effect. Of course I use specific ultrasound liquid and don't include lemi-shine.

It's galvanic corrosion between 2 materials that are far apart on the galvanic series, immersed in an acidic medium.

Iron in the steel goes into solution, liberating 2 electrons.

Fe --> Fe2+ + 2e-

The electrons in this case are likely combining with the hydrogen ions from the acid to release hydrogen gas.

2e- + 2H+ --> H2

Meanwhile the iron cations will combine with something else in the environment, commonly oxygen, to produce a corrosion product that deposits on the brass.
 
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