Stainless Steel Tumbling Media

[Cemetery]

Anybody have any experience with Stainless Steel Tumbling Media?

I thought somebody said steel damages brass over time, but can't recall, but this website says it doesn't.

http://www.stainlesstumblingmedia.com/

[Fox Creek Kid]

Man, that is VERY interesting!!!    Thanks for posting that. 

[Mako]

Cemetery,
I have used steel media (not stainless steel) because I had it on hand.  It worked fine, but since it rusted and I didn't have a mechanical conditioner normally used to prepare the media before use I cleaned the media with acid and then flushed it thoroughly with water before use (you can see why I didn't use it too often).  The shapes I had wouldn't go through the holes but it got in the pockets and cleaned well.  It also didn't get stuck in the cases like my ceramic media does sometimes.

I think it will work fine and it won't work harden the material or damage it in any manner I can think of.  Who told you it would damage the brass?  I'd like to see the reasoning behind that claim.

I usually use ceramic because it is pretty hassle free and I clean several times a month.  The ceramic is slightly abrasive and might work better on really crusty cases.  The steel works by burnishing.

I'd be willing to bet it works fine, and if you get it you will be singing the praises of Stainless media.

That being said, everyone will now go to their corners and defend their own techniques which include ancient Indian beads with opossum fat mixture, corn cob with Danish lump fish powder, Walnut hulls with rouge from circus clown makeup and ceramic with every form of surfactant known to man.

Let the games begin...

~Mako

[Cuts Crooked]

That being said, everyone will now go to their corners and defend their own techniques which include ancient Indian beads with opossum fat mixture, corn cob with Danish lump fish powder, Walnut hulls with rouge from circus clown makeup and ceramic with every form of surfactant known to man.

Let the games begin...

~Mako

LIZARD LITTER!with chunks of catfish fat!

[Fox Creek Kid]

Mako, you're an engineer so answer me this: we all know stainless steel is more rust resistant but not rust PROOF. Would this media not start to rust after a tumbling session unless it was dried 100% or oiled. 

[wildman1]

How about flint shot or glass bead (used for sand blasting), maybe mixed with corncob or walnut media? I would think that small amounts of either one should do a good job. WM

[Mako]

Mako, you're an engineer so answer me this: we all know stainless steel is more rust resistant but not rust PROOF. Would this media not start to rust after a tumbling session unless it was dried 100% or oiled.  

The media is most probably AISI 302 or 304.  Austenitic stainless like that really doesn't rust in the sense you and I are concerned with, if those two alloys are in a high chlorine (usually as chloride ions) environment there will be some pitting, this is why we switch to AISI 316 in those environments.

There are some magnetic finishers and those can't use an austenitic material so they will move to  either a 400 series or PH steel like 17-4.  Those both are not as corrosion resistant, but they are martensitic. The corrosion on those can appear as iron oxide,  the iron is no longer bound up by the chromium.  Unhardened martensitic stainless is less corrosion resistant than the full hardened or material not drawn too soft after hardening.  There is an alloying threshold that frees up some of the carbon and the iron.  Welding or spot heating also causes a problem.

I don't think normal use of a mass finishing stainless material will create a condition where there will be any leaching or transformation of the alloy to the extent it will corrode.  I wouldn't worry about drying it.  I would probably throw in an open shallow container to allow it to dry to prevent organic growth more than anything else.  I wouldn't oil it, just put it in a shallow tray in the sun to dry.

~Mako

[john boy]

Hardness of stainless steel ... http://www.fanagalo.co.za/tech/tech_grades.htm
Hardness of brass ... http://www.metal-mart.com/guides/hardness_brass.aspx

- Won't damage brass.

No Thank You.

[Fox Creek Kid]

Hardness of stainless steel ... http://www.fanagalo.co.za/tech/tech_grades.htm
Hardness of brass ... http://www.metal-mart.com/guides/hardness_brass.aspx 
No Thank You.

Now this is getting interesting. 

[Mako]

Hardness of stainless steel ... http://www.fanagalo.co.za/tech/tech_grades.htm
Hardness of brass ... http://www.metal-mart.com/guides/hardness_brass.aspx  
No Thank You.

It's very simple, just look at the table below. See?



~Mako

[john boy]

It's very simple, just look at the table below. See? 

Mako, good one!

Seriously, consider this folks:  one or more SS slivers that could be overlooked in a case when it is reloaded.  Leading is one thing, but a SS sliver scrapping down the bore is a horse of a different color!  Ceramic media is more forgiving if overlooked and it can happen ...  Especially in bottleneck cases

[Mako]

Mako, good one!

Seriously, consider this folks:  one or more SS slivers that could be overlooked in a case when it is reloaded.  Leading is one thing, but a SS sliver scrapping down the bore is a horse of a different color!  Ceramic media is more forgiving if overlooked and it can happen ...  Especially in bottleneck cases

John Boy,
Okay let's pursue those lines of reasoning.

• Ceramic media is actually larger than the stainless pins
  
  
  
  • You use 2mm straight cut ceramic triangles
  • People who use DD media are using Ø1/8 bologna cut cylinders
  • The Stainless Steel pins are >Ø1/16
• Angular ceramic forms are more likely to bridge in the neck of a case than stainless "pins".
  
  
  
  • See the illustration below using a case that you presently (or have in the past) clean with your Kramer media
  • We use a LOT of medias and the triangles and pyramids will bridge more than rods, balls and elliptical forms

• Ceramic is actually harder than the stainless pins, Kramer calls it proprietary but it is most likely one of the two materials listed below
  
  
  
  • Sillimanite
  • Some other high alumina Al₂O₃ SiO₂ ceramic

Triangles wedge They simply get started with the "points", corners or edges of the triangle contacting the transitions from the shoulder to the neck or shoulder to the body and then have a corresponding chain of locking media bridging to the other side.  Any of us who have used any hard media with angular forms have seen it.  Use it long enough and it will happen.





The updated comparative hardness chart with a few additions:



Regards,
Mako

[Fox Creek Kid]

Mako's right on the "bottlenecking" of the ceramic media per my experiences. I have that trouble often and have merely learned to live with it. This stainless steel REALLY has me interested. I won' worry about a pin getting trapped as I wash, dry & thoroughly inspect all my brass after each tumbling.

[Cemetery]

Mako's right on the "bottlenecking" of the ceramic media per my experiences. I have that trouble often and have merely learned to live with it. This stainless steel REALLY has me interested. I won' worry about a pin getting trapped as I wash, dry & thoroughly inspect all my brass after each tumbling.

Ugh....I have that all the time when I need to tumble 25.20, I've had to disguard a number of brass cause it got so jammed up I couldn't get it unjammed.   

And 25.20 brass ain't easy to comeby.........

[Mako]

Ugh....I have that all the time when I need to tumble 25.20, I've had to disguard a number of brass cause it got so jammed up I couldn't get it unjammed.  

And 25.20 brass ain't easy to comeby.........

Cemetery,
I use a kinetic bullet puller to get the media out if it's wedged.  That usually works...

~Mako

[Deadeye Dick]

Cemetery,
I use a kinetic bullet puller to get the media out if it's wedged.  That usually works...

Good idea, now why didn't I think of that? Guess I just prefer to sit there jamming a small screwdriver in the case in hopes of dislodging them.
Deadeye Dick

[john boy]

Mako - one neat graph and diagram of the 25-20.
re: 2mm's & 25-20's ... Yes, 2 or 3 pieces of media get wedged in less than 1/2 dozen of any caliber.  But not in the necks of the 25-20.  Yes, there will be media inside the cases as there will be with any straight wall and bottle neck.

Take it to the bank ... I have NEVER had a log jam in the neck of 25-20's.  And never a case plugged where I can't remove the media and have tp throw the case in the scrap container.  The media inside the case is removed with a few shakes while dunking the case in the burnishing solution.  The liquid flushes the media out.  With cases that are really filled, just click a couple together and out the media comes

The 25-20's are why I went with the 2mm stuff and have zero complaints with the triangles in any size cases.  So why change!

[Dalton Masterson]

I have been trying the wiggly puppies in my Thumler, but its too hard to get the lid on straight and not leak when they are wiggling.
Any cures???

My initial thought on this was no no no, as steel is harder than brass, therefore it would beat the tar out of the brass.

BUT, with more thought about the subject, I dont think it would matter too much. I think the brass would need discarded due to cracks, boot stomps, etc before the steel would wear through it.

DM

[Mako]

Dalton,
If the material is not harder then it's not going to remove or move anything around.  Even corn cob or walnut hulls are "harder" when they have an abrasive on them.  The cob or the hulls just become the carriers for the abrasive media.  Have you ever just tried using the carrier media without any rouge or polishing compound?  You will get brown streaked brass with a smooth and lustrous brown finish.

The pins act as burnishers just like the burnisher of old used to polish brass and steel before they had the polishes we have now.  Ceramic media as I said before is much harder than brass.  You actually get less abrasion with steel pins than you even do with a lot of metal polish in an accepted carrier like walnut hulls.  I have old .38 super, .40 S&W and especially .45 ACP brass that has been tumbled so often it is worn smooth and the corners are rounded.

The weight of the pins and the relative size means lots of surface contact at any one point in time.  This means less time in the finisher to achieve a finish on the entire surface which means you can run it fr a shorter period and get the brass completely clean.  The longer you run it the more action there is on the sharp edges like the rim corners and case mouths.

It's pretty much as you said you will wear out the brass from stretching it while shooting and then resizing long before you will hurt it by tumbling it for the right amount of time.  I've even heard of some people worried about weakening the brass somehow by work hardening.  It doesn't work that way, it takes plastic deformation to work harden cartridge brass.  If anything you will relieve some of the surface energy by tumbling.

One of the companies I'm associated with does a lot of mass finishing and we are using processes developed over the last thirty years at two other companies we were working in.  We finish ceramic materials and metals.

Regards,
Mako

[john boy]

Gentlemen:  There are several medias that can be used in a rotary tumbler with a burnishing solution to clean and polish brass cases.  If the SS slivers are what you want to use - buy, use it and post pictures of the results

As for me - am completely satisfied with my 2x2mm ceramic triangles capable to clean and polish all my caliber cases.
Here's the results I obtain:

Before - Black Powder Cases


After: cleaning with the 2x2's, Strato-O-Sheen burnishing solution and a 1/2 tsp of TSP (approx 2 hous later)



That's All Folks!