Steel media. what to buy?

[pyrosailor99]

Hi,

i'm buying media for my ball mill.

 

starting from the fact that i know that i could do the best buying Brass cutted rod (expensive) i have the occasion to buy steel balls for a lower price.

 

Well, my store have many different type of steel ball. i wonder what of this are good and what not.

All balls *seems* to be chromed. but i list here the materials:

 

100cr6C85 - AISI 1085

 

100Cr6 AISI 52100 [this are used in bearings] (i would like to buy this. best price.)

 

inox AISI 304 (just for reference, this balls cost more than brass rod!)

 

[other acceptable materials, tell me]

 

 

another question...

i know steel could not be compatible for milling some chem.

could you tell me what chem are incompatible with this balls?

[PersonGuyDude]

Besides the fact that steel sparks, and therefore should NEVER be used with ANY mix of fuel/oxidizer, I personally do not know any incompatibilities that steel has towards individual chemicals.

 

Please, don't even try to mill BP with steel media....

[pyrosailor99]

if i remember right, many of you use stainless steel (inox) media to mill bp...

this is why i asked you this. i don't really know difference between INOX and [100Cr6 AISI 52100] that are anyway chromed...

[dagabu]

Inox AISI 304 can be used with great success in grind chemicals and cleans up better then lead and ceramic. While inox AISI 304 is stainless steel and is not inherently prone to spark, it is not rated as non-sparking. As stated above, these would not be used to grind comps but only single chemicals in a clean jar with clean media.

-dag

[WSM]

Inox AISI 304 can be used with great success in grind chemicals and cleans up better then lead and ceramic. While inox AISI 304 is stainless steel and is not inherently prone to spark, it is not rated as non-sparking. As stated above, these would not be used to grind comps but only single chemicals in a clean jar with clean media.

-dag

 

Actually the US Govt has declared 300 series stainless non-magnetic and non-sparking for their purposes. Armed with this information, a friend of mine got a length of 316 which was cut and the edges rounded, which he uses for milling raw material and grinding BP. It makes meal fairly quickly and (thankfully) won't spark. He's been using it for four years so far and it's still going strong.

 

WSM

[dagabu]

Second time in one day:

 

I'll be damned! My spec sheet does not call out an ANSI non-sparking declaration for Inox AISI 304 material.

-dag

[WSM]

Second time in one day:

I'll be damned! My spec sheet does not call out an ANSI non-sparking declaration for Inox AISI 304 material.

-dag

 

Maybe it was mil-spec? I'm taking other's words on this...

 

WSM

[Mumbles]

In either case, I wouldn't want to have it anywhere near anything that I care about. There are always freak accidents. I've read of people using SS with success for years, just as I've read of people using ceramic for years. I've gotten to the point that I'd trust ceramic materials of a known and qualified source.

 

The first you listed is a carbon steel, the second is a chromed steel but not stainless. The third is the one I'd probably go with if I had any thoughts of using it on BP. The second is the one I'd go with if I were just grinding chemicals.

[dagabu]

I had an unrelated question for MNOSHA (Minnesota's OSHA branch) today about reporting records and asked about non-sparking and was read the OSHA definition stating that there were no stainless steel grinding media approved for use in type T environments (charcoal dust).

 

I don't know how that relates to us but that is their spin.

 

-dag

Edited August 4, 2011 by dagabu

[stckmndn]

In either case, I wouldn't want to have it anywhere near anything that I care about. There are always freak accidents. I've read of people using SS with success for years, just as I've read of people using ceramic for years. I've gotten to the point that I'd trust ceramic materials of a known and qualified source.

 

The first you listed is a carbon steel, the second is a chromed steel but not stainless. The third is the one I'd probably go with if I had any thoughts of using it on BP. The second is the one I'd go with if I were just grinding chemicals.

 

It's funny. It was a post of yours that made me relax enough to buy the Zirc M from the link from oldguy. And it's also you that makes me the most nervous about it. So, a pit has been dug to proper dimensions and the mill operates from there. Feel much safer now. And it hasn't blown up yet. I hope to keep you posted.

[Mumbles]

If it makes you feel any better it wasn't a mill that caused my accident. I dunno man, I'm still a bit uneasy about certain things, but the Zirc media still seems okay. Anything I make in the future will be very far away from everything. If I really felt like throwing tesla coils in there I really could if I wanted.

[stckmndn]

Thanks for your thoughtfulness, Mumbles. You're always a great help.

[pyrosailor99]

Mmmmm.... so strike out Steel from my list of cheap media...

 

Unfortunately i'm unable to build my self Brass Tube filled with Lead and Pressed at XXXX psi as *SOMEONE* did :whistle:

 

So i'm searching desperately a source for media. I found a seller of ceramic media, but i watend avoid it for light flash about i read on this forum... anyway creamic media are to lightweight and this would increate millin time of BP. I want to do the BP in less time because less time seems to be = less exposing time to risk (any risk, to be viewed from others, to break my ears, to explode all, etc etcc).

 

I've just eared since some day of Zirconia Media...

can someone make a summary of this material?

risks?

weight?

is good to buy it as 'USED'?

does it leave traces in the chems?

does it react with some chem?

Zirconia media are intended as Zirconia Oxide Media?

YSZ media are really better?

 

i know there is much to read in this forum (and i read it about - all positive seems.) but it would be good to make here a point on this argument also for future readers.

 

thanks all!

[dagabu]

Mmmmm.... so strike out Steel from my list of cheap media...

 

Unfortunately i'm unable to build my self Brass Tube filled with Lead and Pressed at XXXX psi as *SOMEONE* did :whistle:

 

Copper tube

[oldguy]

So i'm searching desperately a source for media. I found a seller of ceramic media, but i watend avoid it for light flash about i read on this forum... anyway creamic media are to lightweight and this would increate millin time of BP. I want to do the BP in less time because less time seems to be = less exposing time to risk (any risk, to be viewed from others, to break my ears, to explode all, etc etcc).

 

I've just eared since some day of Zirconia Media...

can someone make a summary of this material?

risks?

weight?

is good to buy it as 'USED'?

does it leave traces in the chems?

does it react with some chem?

Zirconia media are intended as Zirconia Oxide Media?

YSZ media are really better?

 

i know there is much to read in this forum (and i read it about - all positive seems.) but it would be good to make here a point on this argument also for future readers.

 

thanks all!

 

I use Zirc M with great results.

New, it is very expensive.

Sometimes, you can find it used on ebay @ better prices.

 

 

NEAR NEW

 

USED

 

Mg/Al

 

1/2" Radius end cylinder.................... 65 PCs/lb

With a specific gravity of 3.42, the charging factor of Burundum (pounds of media to be used per gallon of total jar capacity to give a 50% vol. Media charge) is approximately 9 lbs/gallon.

 

Zirconia “M” Grinding Media

 

http://www.usstonewa...om/products.htm

 

Magnesia Stabilized Zirconia grinding media mills twice as fast as equivalently-sized alumina media with only 1/2 the media weight loss and only 1/3 the wear (weight loss) of the grinding jar, with accompanying reduced batch contamination. Available in radius end cylinders, with length equal to their outside diameters. Features: 1.6 times denser than high alumina, Hard, non-porous surface, chip resistant, easily cleaned., Non-conductive, non-magnetic, excellent resistance to mechanical and thermal shock.

[pyrosailor99]

Ok, just asked some extimation for YSZ zirconia medias... i hope this kind (YSZ) is good as Zirconia M or also better.

 

i will anyway try to get it on ebay as first extimation are to high... for that price, cut Brass rods is much cheaper!

 

;-)

[dagabu]

Here is a link to some great media.

 

LINK

 

-dag

[pyrosailor99]

With a specific gravity of 3.42, the charging factor of Burundum (pounds of media to be used per gallon of total jar capacity to give a 50% vol. Media charge) is approximately 9 lbs/gallon.

 

So, my jar would be approximatively 5 liters (just a few more than a US gallon) i think i can buy a kit of 20lbs and store remaining for future.

 

Here is a link to some great media.

Wow! thanks!

I couldn't find it as shipping is only for US, but i will ask for different shipping!

 

PS. diameter is about 0,9cm. do you think it is really good for milling? i've read on a famous source the ideal diameter for media is 1 inch for jars like mine.

 

 

thank you!!

[oldguy]

So, my jar would be approximatively 5 liters (just a few more than a US gallon) i think i can buy a kit of 20lbs and store remaining for future.

PS. diameter is about 0,9cm. do you think it is really good for milling? i've read on a famous source the ideal diameter for media is 1 inch for jars like mine.

thank you!!

 

 

This is one of my 8 inch diameter ball mill jars.

It is roughly 1 US gallon.

I run 1/2 inch Zirc M in it.

But, 3/8ths would work well.

 

Zirc media is very heavy. I don't think you will need to store any.

20 lbs may not even be enough to fill your jar 1/2 way.

 

1 inch media in a jar this size would be very large.

[pyrosailor99]

i'm a bit confused because you said

With a specific gravity of 3.42, the charging factor of Burundum (pounds of media to be used per gallon of total jar capacity to give a 50% vol. Media charge) is approximately 9 lbs/gallon.

 

so if my jar i just a bit more than a gallon... i should need just a bit more than 9lbs of media (if i understood well)

 

then you said

 

20 lbs may not even be enough to fill your jar 1/2 way.

 

so now i'm confused....

can you explain?

 

thanks!

[oldguy]

I am mistaken. I had my head in my ass & was thinking about a 4 gallon jar, NOT a 1 gallon jar.

[pyrosailor99]

LOL LOL LOL :lol:

 

no problem my friend!! all of us some time have the head in the ... LOL!!

you made me laugh so much!! thanks guy!

[Mumbles]

I've been under the impression that the zirconium media is denser than alumina products. It takes around 10-12lbs the last time I checked to properly charge a 1 gallon jar. I would have expected the zirconium to run in the vicinity of 15-18lbs.

 

Yes, you'll be fine with using 1/2" media. I'm sure you've heard the 1/8 the diameter "rule". It works for 4" and 6" pretty well, but honestly the size doesn't really need to increase after that. I've used jars around 24" in diameter before. Do you really think we used 3" balls in there? No, we still used 1/2". A larger amount of smaller media over a certain size grinds faster and better. More collisions per turn and all that. This is just one of the reasons that bigger mills are more efficient.

[pyrosailor99]

OPS!

 

well i've just got a Protein Jar of 20cm ID x 25cm lenght - abouit 7,5liters (about 2 US gallons)...

 

in my calculations on this basis:

 

With a specific gravity of 3.42, the charging factor of Burundum (pounds of media to be used per gallon of total jar capacity to give a 50% vol. Media charge) is approximately 9 lbs/gallon.

and

 

Name .Major Material - Density - Hardness - Color- Sizes (mm) - Pieces Per Pound- Charging Factor

Zirconia-M - ZT0, - MgO- 5.4 - 8- Tan - 3-5 - N/A- 14

 

i should need 12,5kg (about 30 pounds) of zirconia m media to fill 50% of the jar.

 

But i'm very not confindent in this because in the sentence up i read "Burundum" . Is burundum the same of Zirconia M? i think not... but googling not helped me in clarification of this.

 

in the end... will 20 pounds of 3/8inches zirconia m media be enough to fill my 2gals jar?

 

please reply me ASAP as i'm placing the order and i need to know if i have do duplicate quantity and shipping costs!

 

thanks!

Edited August 8, 2011 by pyrosailor99

[oldguy]

"burundum" = grinding media

Zirc M = grinding media.

 

I would not use a protein jar as a ball mill jar.

it may work for a short while, but will wear thin & crack.

That will cause leaks.

Which is a bad thing.

 

My small digital scale will only weigh up to 4 lbs.

My 50 lb electric scale is broken.

I will buy or borrow a larger scale today & weigh 1 gallon of Zirc M.

Edited August 8, 2011 by oldguy