Polishing nickel deposits off a carbide sizer

[kevin c]

I ran a bunch of nickel plated brass through my carbide 9mm sizing die. Never had a problem before but this batch of 2500 was unusual in that it had turned a gray color after cleaning in citric acid (it’s that purple lacquered Winchester training ammo), and there must have been some flaking and nickel deposition on the die because now I’m getting vertical scoring on the cases.

So, what’s the best way of polishing off the deposits? Rouge? Flitz or JB bore paste? Is a carborundum containing valve grinding compound too aggressive?

All suggestions and comments welcome.

[JimB..]

I ran a bunch of nickel plated brass through my carbide 9mm sizing die. Never had a problem before but this batch of 2500 was unusual in that it had turned a gray color after cleaning in citric acid (it’s that purple lacquered Winchester training ammo), and there must have been some flaking and nickel deposition on the die because now I’m getting vertical scoring on the cases.

So, what’s the best way of polishing off the deposits? Rouge? Flitz or JB bore paste? Is a carborundum containing valve grinding compound too aggressive?

All suggestions and comments welcome.

I use a little kroil and a bronze brush in a drill.

[dale2242]

Nickle plated brass never gets the wet treatment in my shop.
It cleans very well with dry media in a vibratory tumbler.

[country gent]

Valve grinding compound is way to aggressive in a die, it will not give the surface finish and actually remove metal. I would try a mild scotch brite pad by hand first. The the flitz or simichrome type polishes. Another Ive had good results with as a cleaner polish is tooth paste. Another to try is rubbing with a hardwood dowels edge as a scrapper, this works better if you can see the deposits.

If all else fails very fine diamond compound or lapping compound in the 1000 grit or above.

[Brassmonkey]

Nickle plated brass never gets the wet treatment in my shop.
It cleans very well with dry media in a vibratory tumbler.

This purple stuff is weird. It looks like Nickel plated with a purple tint almost anodized but turns gray steel looking with citric acid wash. With aggressive tumbling the gray comes off and leaves a bronze looking shell.

[Bmi48219]

I had the same thing happen on a steel sizing die. Brass brush didn’t seem to be working so I wrapped a dowel with crocus cloth and slowly spun it in the die with my drill for 3 seconds. Scratches vanished and brass sized afterwards still slid easily into the chambers / cylinders of my 38’s.
The damage had occurred after only sizing a few nickel cases. Never again.

[mdi]

For metal polishing with out removing metal I have used Comet Cleanser or Bar Keeper's Friend made into a paste with light oil. I have polished several molds, a couple dies and some handgun innards with it. I have never had any nickel cases deposit nickel on any sizing die and I just run them through my dry tumbler less than hour (the wax in my media makes the cases, both brass and nickel,a bit slicker). None of my nickel cases are "purple" (Winchester training ammo)...

[GregLaROCHE]

I’m beginning to think that nylon brushes are better for removing deposits than bronze bushes. Maybe it’s where you buy them or they just aren’t as stiff as they used to be.

[kevin c]

Thank you all.

I’ve used scotch brite on expanders but working inside the carbide ring might be problematic. Maybe an appropriately sized wood dowel would help. The ring spins in the die body so unless I can find a way of immobilizing it I’ll get poor scouring/polishing from a drill.

Bmi48218, was that a fine grit crocus cloth, 320 or thereabouts? Having some Flitz or Simichrome around generally seems a good idea. Comet I haven’t had around since I was a kid, and that was well back in the previous century, but I remember how gritty it felt and how well it cleaned up porcelain. Maybe worth a look around for.

Many good suggestions: thanks again!

[country gent]

If the carbide ring is spinning it loose either from wear or a crack. This can be a problem in and of itself. to imobilize it a couple light drops of green loctite or super glue on the seam may wick in to the gap.

[Bmi48219]

Bmi48218, was that a fine grit crocus cloth, 320 or thereabouts? ….

Kevin, the sheet back says ‘Carborundum Flexback Crocus Cloth R J135E’
It is far less abrasive to the touch than the 600 grit paper I have. Don’t know if it will work on carbide. My die was steel. Good luck

[ReloaderFred]

I use what Varmint Al recommends, and I've restored quite a few dies for both myself and friends.

Here's the link: http://varmintal.com/arelo.htm#Polish

Hope this helps.

Fred

[kevin c]

Country gent, thanks for the suggestion. The ring doesn’t look cracked, but I’ve used it to size over 100K cases so wear certainly is a consideration. I’ll try the loctite or superglue; immobilizing the ring should make my polishing attempts a bit more effective.

Bmi48219, good to get your comparison on grit feel. I’m thinking of trying something really fine to avoid removing metal.

ReloaderFred, that was a nice read. I’m just a volume pistol shooter who only needs 2” groups at 25 yards, so the ultra detailed approach won’t do much for my shooting. Still, that kind of attention to detail scratches my OC itch, and I have a magpie’s love of shiny stuff, so I see a tube of Flitz on my work bench soon.

Thanks all!

[ReloaderFred]

kevin c,

You can also use J-B Bore Cleaner in place of the Flitz, if you happen to already have some on hand.

Hope this helps.

Fred

[1hole]

...there must have been some flaking and nickel deposition on the die because now I’m getting vertical scoring on the cases.

So, what’s the best way of polishing off the deposits? Rouge? Flitz or JB bore paste? Is a carborundum containing valve grinding compound too aggressive?

First, a softer metal rubbing hard against a harder metal will cause galling small deposits of the softer on the harder. The galled bits will then score any later parts. Standard sizer dies are case hardened steel so bits of poorly lubed brass cases will adhere to the die walls, especially around the neck and cause scratches; ditto dry carbide sizers will gall. Just a little bit of some sort of lube will do a LOT to avoid case galling/scratching no matter what cases or dies we use.

Removing the galled bits will require some level of "grinding", polishing with anything won't do much. Fortunately, even steel dies are so hard that it's very difficult to harm them and it takes something with diamond dust to affect carbide at all.

I've long used homemade tightly fitted wood dowel laps wrapped with Walmart's auto dept 400 and finer grit black (carborundum) abrasive paper chucked in an electric drill to clean and perfectly restore used "scratched" sizers. How long it will take such laps to remove galling from a die depends on how thick the galling is and how fast the drill spins but it commonly takes me from 10 to 25 minutes to clean out an abused die.

I've found that a dull matt finish in a steel die will better hold a tiny layer of case lube and make work easier than polishing the interior to a mirror finish. Nothing but diamond paste will change or polish a carbide sizer ring.

[kevin c]

You may be right there, 1hole, about polishing not doing much. I just tried both JB bore paste and Flitz on felt pellets chucked into and spun in a drill (after using green thread locker). ‘taint feeling’ the love: the deposits are still there, and the rest of the carbide still has the same haze I saw originally but had ignored (more galling I think [my other used carbide sizers from the same manufacturer are mirror bright], just not as bad as what scratches the cases). I’d tried some 1000 grit on an undersized dowel, hand run, with no change, but, by your description of the process, I probably had too little contact for too little time and with maybe also too fine or soft an abrasive.

I’ll keep at it.

[Brassmonkey]

Looking at the ones I pulled out during the washing & tumbling process. I wonder if an xrf scan would be of any value. Just what are we dealing with?

301744

[kevin c]

Don’t know for sure, but I can say that there is brass colored metal underneath and that it’s non magnetic. A sort of chemical tarnish, related to the plating, the lacquer on it and/or the washing process we put it through, but I don’t know what.

[jetinteriorguy]

I wonder if any copper removing type cleaner would take off the brass?

[country gent]

There is a process known to as scrapping where a small sharp tool is usedto remove high spots slowly and carefully. You might look into this a small 3 cornered file ground into a small scrapper very sharp and polished, go after the deposits one at a time peeling them out. the scrapper wont touch the carbide ring. would be tedious work but it would will remove the build ups. General also makes one of these small bearing burr scrappers.

[nicholst55]

What brand is the sizing die? If it has a lifetime guarantee, I think I'd be contacting the manufacturer. But that's just me.

[kevin c]

Jetinteriorguy: I’m thinking the deposits aren’t brass, given how they only showed up after working with these particular gray cases, and after 100K regular yellow brass through the die not doing the same.

Country gent: like using a dental scraper? Maybe I could scrape with a Dremel burr by hand, mounted on a file handle. Edit: I think I found what you’re talking about. Not very expensive on line and more appropriate to the task than my jury rigged proposal. I see straight and hooked blades. Straight seems best for the inside flats of the ring where I see the lines of galling.

Nicholst55: the die is fine. It’s just that there’s hard to remove crud on it. Not Dillon’s fault, but mine for running a couple thousand funky looking cases through it without lube.

I should admit that the lines of galling do seem a little fainter after all I tried before, but I still feel some roughness when running the end of a wire around the carbide ring interior. Trial sizing notes less marking, especially on lubed cases. Am I right in thinking that galling tends to progress unless removed completely?

[bruce381]

Hi Kevin

I have used a cheapo diamond plated dremel polishing tip from amazon comes in various sizes.
Works well diamond is about only thing that can polish carbide and amount if any removed will not be measurable.
I would be more worried about the loose carbide ring than anything, but 9mm dies are hard to find at a decent price right now.

[jetinteriorguy]

Jetinteriorguy: I’m thinking the deposits aren’t brass, given how they only showed up after working with these particular gray cases, and after 100K regular yellow brass through the die not doing the same.

Country gent: like using a dental scraper? Maybe I could scrape with a Dremel burr by hand, mounted on a file handle. Edit: I think I found what you’re talking about. Not very expensive on line and more appropriate to the task than my jury rigged proposal. I see straight and hooked blades. Straight seems best for the inside flats of the ring where I see the lines of galling.

Nicholst55: the die is fine. It’s just that there’s hard to remove crud on it. Not Dillon’s fault, but mine for running a couple thousand funky looking cases through it without lube.

I should admit that the lines of galling do seem a little fainter after all I tried before, but I still feel some roughness when running the end of a wire around the carbide ring interior. Trial sizing notes less marking, especially on lubed cases. Am I right in thinking that galling tends to progress unless removed completely?
Ah, silly me. Your reply in post #18 was stuck in my head, I now realize you were replying to the previous post, not referring to your situation.

[1hole]

Looking at the ones I pulled out during the washing & tumbling process. I wonder if an xrf scan would be of any value. Just what are we dealing with?

301744

What we're dealing with is straight wall case resizing dies without being specific about that. Your photo is looking at cast bullet lubracator/sizing dies. :)

[1hole]

... the die is fine. It’s just that there’s hard to remove crud on it. Not Dillon’s fault, but mine for running a couple thousand funky looking cases through it without lube.

The "problem" is that even carbide sizers need some small amount of lube. Dry, hospital clean and shiney cases simply aren't what TC dies need. Carbide sizers came before viberator cleaning and polishing which removed the tiny bit of condensed smoke and traces of bullet lube on fired cases so the claimed "no lube needed" was true at the time! But, with the eventual arrival of tumblers, that time has changed and a little case lube helps, a lot.

Sadly, few of today's gurus tell anyone any difference ... and I suspect a lot of them just think their own dies have been scratched by 'dirty cases'!


Am I right in thinking that galling tends to progress unless removed completely?

You are right. Each bit of die wall galling attracts a bit more metal each time it's used and the 'scratches' keep growing.

[ulav8r]

Scrapping is when I take junk metal to Cunningham Recycling and sell it to them by the pound. Scraping is using an edged tool to scrape anything from the surface it is on, whether it be brass in a die or icing on a cake. Of course the icing can be scraped off with a finger or spoon.

[Brassmonkey]

What we're dealing with is straight wall case resizing dies without being specific about that. Your photo is looking at cast bullet lubracator/sizing dies. :)

My photo Terrible as it is, is of the purple win training ammo brass that I pulled out at different points of the washing & tumbling process.

Right to left
Untouched
First wash
Longer wash
Tumble
Longer tumble
End of tumble

What we are dealing with is a brass case with 4 layers of stuff on them. Now some of that stuff is stuck in op's die.

[1hole]

My photo Terrible as it is, is of the purple win training ammo brass that I pulled out at different points of the washing & tumbling process.

Ah, I stand corrected and see it now.

I didn't have my reading glasses at the time and thought your photo was of a collection of dirty Lyman bullet sizer dies.

[Noah Zark]

Being familiar with the metal finishing industry, I'm reading posts in this thread regarding the use of citric acid to clean cases. While mild or buffered acids can be used to clean and de-tarnish / deoxidize brass, PLEASE TAKE NOTE that acids will remove plating, including nickel. In fact, it is common rework practice in plating shops to briefly soak substandardly plated parts in acid to strip them for replating.

Exposing nickle-plated cartridge cases to acid is asking for trouble.

Noah

[kevin c]

Noah Zark:

I know from personal use that a very few drops of pool acid (HCl 28-36% or a bit under molar concentration) is enough to rapidly take the tarnish off a FART drum’s worth of regular yellow brass; way too strong and hard to control. I switched to citric acid as what I thought was an orders of magnitude less aggressive alternative.

I was under the impression that nickel plating was put on for corrosion resistance. With that and the weaker acid I never considered I might be chemically stripping the nickel.

I’ve personally seen this color change with citric acid wet tumbling only with Winchester purple nickel, though I’ve found Tula pistol cases looking the same (steel?). No issues that I’ve found with other nickel cases cleaned the same way.

Update: there are still visible lines on the interior of the sizer, but, lubed, there isn’t any scoring on the cases. I’ll finish sizing what remains of the gray brass. I’m determined to get the galling out, so I’ll go back to it afterwards. I’m planning on trying sand paper on tight dowels or maybe even diamond paste on felt. If it builds up badly again I’ll try a scraper first.

[ulav8r]

Silicon carbide sand paper would probably cut the nickel from the die much more quickly than most others, diamond would also cut the carbide.

[kevin c]

Well, fine valve grinding compound on felt polishing bits chucked into a drill did absolutely nothing (that’s usually carborundum, right?). I think 1500 grit diamond compound is next. I’ll be slow and careful.

[JimB..]

I have a Dillon 41 mag die that’s galling, they suggest 600 grit paper rolled up to clean it up…and to return it if that fails.

I wouldn’t go for a finer and harder grinding compound. The galling is not carbide, you don’t need something that will cut carbide to remove it.

[kevin c]

Update.

With the carbide ring now held tight by green Loctite, I chucked a split 3/8” dowel in a hand drill and wrapped enough 800 grit carborundum paper through the slit and around the dowel to make a snug fit in the ring. Repeated low speed short pulses until quite warm followed by cooling, totaling five minutes running time, made the lines lighten a little more than all the prior approaches together. The haze was not changed at all.

I decided to risk using diamond grit. I put a dab of 25% 1500 grit on the already used carborundum paper still on the dowel and ran only 5 three second pulses at low enough rpm’s that there was no heating of the die body, though the oil based paste liquified and immediately turned black. Wiped clean, the ring now had no lines at all, and was smooth with a light matte surface. I then used a bit of 25% 5000 grit on VFG pellets (9mm version, which I think are 9.3mm) also a snug fit, and ran that on screw jag chucked in the drill for about 30 seconds. It came out a little blackened, but now the carbide ring interior is mirror bright and completely free of any visible galling.

So the diamond grit was fast and effective, but maybe too much of each. I don’t think I hogged out the die, but, compared to the slow, laborious and relatively ineffective techniques I tried first, the diamond grit definitely needs a light, cautious touch with very short run time (at least with the grit sizes and concentrations I used; maybe lower concentrations and finer grits would be less aggressive).

Thanks to all for your help. I now have a useable die that I will run only lubed nickel brass through (;^]).