Stainless steel brass polishing

[wileybelch]

I started a thread on this subject back in late Dec 2014. A lot of useful info was offered by several members. Several comments referred to a Lemi-Shine product as an additive to the tumbler gemish to make the final brass shine (rather than a dull, clean appearance). I went to WallyMart and found at least 5 different Lemi-Shine products on the shelf (in the cleaning products section). They all claim a 'citrus' ingredient, but no mention of concentration. To get true citric acid (a powder), you have to go to the canning section where small jars of citric acid are offered for the home canning crowd. In the meantime, if anyone knows exactly which Lemi-Shine product works for the stainless steel procedure, let us know.
Note: the current recipe is still 5lbs ss pins + 3.5lbs brass with a squirt of Dawn and only enough water to cover the brass. I'm going to do a batch of .44 Mag brass today using 1tblsp citric acid powder. Stay tuned...

 

[Bayou]

Lemi-Shine had a product name change a while back. The one used for tumbling used to be called "Lemi-Shine Original". About 2 or 3 years or so ago, this name was changed to "Lemi-Shine Booster".

I called the company and spoke to a CSR about this. She told me the products were exactly the same, and the name change was a marketing move only.

Here's the current product:

https://www.lemishine.com/products/detergent_booster/

Hope this helps -

Bayou

 

[hdwhit]

wileybelch wrote:
I'm going to do a batch of .44 Mag brass today using 1tblsp citric acid powder.

I'm not sure how much water constitutes "only enough water to cover", but I am guessing it is less than a gallon. With a full tablespoon of citric acid you have a fairly concentrated weak acid solution and may want to limit your tumbling time otherwise your brass will come out dull or even in a tan-like color.

If that happens, you can tumble the cases again with a much lower amount of citric acid and get the shine back.

 

[cw308]

I clean with the wet Tumbler B Tumbler with Stainless Steel Pins , I asked my wife why she's didn't use Dawn detergent , she said Sun detergent works better then Dawn. After using the Dawn for awhile I tried the Sun , she was right the made the brass clean & brighter.

I also use very little LemiShine Original , too much will turn your brass a pinkish color, two table spoons of detergent an just the tip of the spoon of LemiShine , you may not even need the LemiShine , right now I'm tumbling brass without it , I will let you know how it works .

I changed to wet tumbling. after 30 years , I just like how it remover the carbon from the inside of the case & primer pockets .

I cleaned without LemiShine , the brass looked just as bright.

 

[T. O'Heir]

"...how much water constitutes "only enough water to cover"..." Same as it does for potatoes.
All this wet, SS pins, brass cleaning is more trouble than it's worth. No polish or dish soap is necessary with a dry tumbler. Throw the cases in, turn it on, cover it with a cardboard box to supress the noise(or close the door for the rich people) and leave it for a couple hours. Done.

 

[cw308]

With the wet tumbler the water is 1" from the top . I just like the wet method much better , the brass comes out much cleaner , its not a problem for me to drain the water & wipe off the cases , I let them dry in the store bought plastic ammo holders 20 to a box , I'll tape 3 together giving me 60 spaces

I reload 30 rounds , so the bottom 3 rows are empty , allows me to change from top 3 to bottom when sizing , trimming & priming . Charging and seating I use a tray, cases are face up then . If dry works for you that's fine to , only do what's right for you . I'm starting to sound like a poet .

 

[RC20]

I have it on very good authority that this works gangbusters

https://www.shootersconnectionstore.com/CED-Brass-Tornado-Pro-Series-Tumbler-P3659.aspx

Fruit dryer from Wal-Mart to dry it when done.

 

[FrankenMauser]

Citric acid can be ordered in much larger quantities, if desired.
And restaurant supply or baking shops, also often have it available in 1/2 to 10 pound quantities.

In bulk, it's far cheaper than buying Lemi-Shine.

I bought 5 lbs about six years ago, for brass cleaning and to make some reactive targets. (Re-pressurizing aluminum containers with water, and citric acid and sodium bicarbonate in a 'time-release' capsule.)
After various experiments, about 40 targets, brass cleaning, miscellaneous cleaning, some use in the kitchen, and a few 'supercharged' paper-mache volcano eruptions for the kids, I still have at least 3 lbs...

 

[Bayou]

"Citric acid can be ordered in much larger quantities, if desired.
And restaurant supply or baking shops, also often have it available in 1/2 to 10 pound quantities.

In bulk, it's far cheaper than buying Lemi-Shine"

I've never used citric acid over Lemi-Shine, so I'm not sure of the amount of citric acid is used per batch of brass. (By "batch", for me, that is roughly 5 pounds of brass, plus or minus a pound or two.)

About how much citric acid would be added to a batch of about this size?

As far as the Lemi-Shine goes, for a batch of brass the size I've described, I use 1/4 of one TSP. I've been using the same container of Lemi-Shine for 5 years now, and that hasn't put much of a dent in the contents. I'll probably retire on the same container of Lemi-Shine....

Bayou

 

[wileybelch]

Another report

So I tried several more batches using different amounts of brass by weight.
I used up to 5lbs of .44 Mag brass with the 5lbs of SS pins plus a squirt of Dawn and 2tsp Citric acid powder. Enough water to just cover the brass in the Frankford Arsenal tumbler. Tumbled for three hours (while I mowed the grass). Over a dozen cases with nasty green corrosion came out clean (near new looking). This formula produces bright, polished brass with no oddball colors. I did the 3hr run because I had the time and some of the brass was pretty ugly; your needs may vary.
NOTE: I suggest the following steps in this polishing process
1) Decap cases before tumbling(this assures that the water sloshing action during tumbling is able to wash through the case without restriction which then thoroughly cleans flash holes and primer pockets.
2) Decapping also aids rapid drying (I rinse the brass through a colander and lay my wet brass out on cookie sheets and air dry on a picnic bench). SS with primers still in cases quarantees that water will be able to react with residual salts left in the primer/primer pocket leaving white deposits around the flash hole (as the water dries/evaporates) that won't be seen until decapping. Most people will not realize the crud that is left in their flash holes during reloading and these residues may contribute to erratic ignition with the new primers. This situation may be an unnecessary concern.
3) Do not mix brass calibers that may get stuck in each other, ie., don't mix 9mm/38/357 with .45ACP/.45Colt.
4) I used to use a corn cob/walnut dry vibrator for years before discovering the wet SS tumbler tool. The SS technique is far superior. Despite the extra effort with the SS, the finished brass is worth it.
5) Almost all my experiments with the SS were done with straight-walled pistol calibers.
6) SS polishing will not remove road tar or straighten bent cases.
PS: suggestions above will be tested and results passed on with each new batch of brass.
Thanks everybody...
OOPS, almost forgot. When filling the Frankford tub (after pins, brass, and water added), be sure to shake the fully filled tub sideways vigorously. The SS pins and brass need to be thoroughly intermixed before putting the tub on the tumbler. Otherwise, you can inadvertently stratify the pins and brass greatly decreasing efficiency.

 

[mete]

Pinkish brass ? The brass is a copper/zinc alloy .If you etch away some of the zinc the brass can look 'pinkish'. Shouldn't be a problem as it's only on the surface !

 

[hdwhit]

T. O'Heir wrote:
"...how much water constitutes "only enough water to cover"..." Same as it does for potatoes.

Well, if you have two potatoes in a one quart pot and add just enough water to cover, you have a very different amount of water than if you have a cauldron full of this year's harvest.

The point was that a tablespoon of Lemishine is going to yield a different concentration if used in a quart of water versus a gallon - and with the quart the brass will turn pink/tan in a short amount of time.

 

[hdwhit]

FrankenMauser wrote:
In bulk, it's far cheaper than buying Lemi-Shine.

Granted.

But, a bottle of Lemi-Shine will last me for about a year, my wife doesn't object to it being stored under the kitchen sink, and she is comfortable using it as a dishwasher cleaner (as opposed to some nondescript white powder), so for convenience and domestic harmony, Lemi-Shine it is.

 

[hdwhit]

wileybelch wrote:
NOTE: I suggest the following steps in this polishing process
...
4) I used to use a corn cob/walnut dry vibrator for years before discovering the wet SS tumbler tool. The SS technique is far superior. Despite the extra effort with the SS, the finished brass is worth it.

Not so much a step in the process as a commentary on it.

IF you value a "jewelry grade" shine on your brass, then metallic pin tumbling is definitely the way to go and I'm glad that it is delivering the kind of results you expect.

But, I don't place much value on how shiny my brass is. I want my brass clean enough and with enough tarnish removed to facilitate a thorough visual and instrumented inspection of the case and to not scratch my dies. Beyond that, I don't much care what the reflective index of the case happens to be.

This is why I settled on a process of washing (not tumbling) cases in an acid/detergent solution. The cases are later dry tumbling in a rotary tumbler after resizing to remove the lubricant.

 

[wileybelch]

For HDWHIT

On the issue of amount of water and polishing additive: I don't know exactly what chemistry is happening with the citric acid treatment. Therefore, I can't say whether the addition is concentration dependent or not. Nonetheless, whether I use 1/2 gal or a full gal of water to cover the load, I use two tsp of citric acid powder per batch (3 tsp if really corroded).
I agree with your use of dry vibrator cleaning/polishing - UP TO A POINT. If my brass is bright and sparkly shiny after the SS process, I can get 1 or 2 reloads using only corn cobs or walnut media to 'freshen' the brass for clean cases (and it's much faster than SS!). By the third reload, however, powder blowby residues usually stain the brass to the point that SS is needed to return the brass to full 'shine'. Caution: with corn cobs do not decap brass before vibrating. Exposed primer pockets are prone to lodging bits of cob in the flash hole/primer pocket and may not be detected during loading. Decapping after dry polishing usually removes any stuck cob during subsequent decapping. This is particularly aggravating with large rifle cases where flash holes often have severe burrs inside the case (its these burrs that the cob particles stick to). Pistol cases rarely have burrs.
On the water issue, the water is used to create a slurry of brass and SS pins. Too much (beyond the filling just to the brass level) quickly reduces the intimate abrasive nature of the slurry thereby reducing the efficiency of the polishing action.

 

[cw308]

wileybelch

I also have changed to wet tumbling , I found Sun detergent works better then Dawn, thanks to my wife . Two tablespoons but I use very little LemiShine , l remember reading more LemiShine is used if you have hard water in your area. If I use over 1/4 teaspoon my brass has a pinkish look , less works better for me an some times I just use detergent .

I start out by covering the pins with water add the soap & LeniShine and mix , then add brass and water , fill water 1" from the top of the tumbler. Will never go back to dry.

 

[hdwhit]

wileybelch wrote:
I don't know exactly what chemistry is happening with the citric acid treatment. Therefore, I can't say whether the addition is concentration dependent or not.

I am familiar with the reduction reaction that does occur when oxidized brass is exposed to a weak acid.

The "tarnish" on the surface of brass is an oxide of copper. The acid "reduces" the oxide by liberating the oxygen so that what remains is the metallic copper that was originally part of the brass alloy. If the brass is left in the acid long enough that all of the oxidized copper is reduced, the acid will begin to react with the copper and/or zinc from the alloy leaving a dull finish or even a change in color.

This was the point of my original response to your post. Depending on the amount of water you are using, you have a fairly concentrated acid solution and if you leave the brass in that solution for a prolonged period of time, then regardless of what media you are using, you risk ending up with a dull finish or even brass with strange colors.

Citric acid, Acetic acid, Oxoleic acid all have similar properties and will work about the same.

I agree with your use of dry vibrator cleaning/polishing - UP TO A POINT.

Thank you. It's very gratifying that you agree, but you seem to have missed the point that I DON'T use a vibratory cleaner; I use a rotary tumbler.

Still, as I said in post #14, it appears our objectives in polishing brass are entirely different, so I don't expect us to have any agreement as to approach or methodology.

By the third reload,...

All of my brass is processed the same way each time.

Caution: with corn cobs do not decap brass before vibrating. Exposed primer pockets are prone to lodging bits of cob in the flash hole/primer pocket and may not be detected during loading.

I decap all of my brass before cleaning. I use walnut media for the dry portion (which comes after the brass has been resized). Both walnut and corn cod media can get lodged in the flash hole. That is not a problem because:

1. The flash hole is visually inspected before the new primer is seated and if there is media in the flash hole, it is dislodged.
2. Even if the media were left in the flash hole, it is unlikely anyone would ever know. When lead styphnate ignites, the explosive wavefront it generates moves at about 16,000 feet per second so a piece of corn cob held in the flash hole by friction will be pushed into the case to join the powder where it will either be burned up or ejected out of the muzzle.

 

[Chainsaw.]

I just started SS tumble cleaning, built a rig out of a 5 gal propane bottle and an old electric motor. I have to say this is a FANTASIC way to clean brass. My cleaning time is maybe 1/8th the time it uses to take with dry media, plus no nasty dust. The brass come out sparkling clean outside AND inside. I cleaned 5x as much brass in less than the time it use to take to clean a batch with dry media.