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media in ball mills


tentacles

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Any reason why marbles couldn't be used as a low cost ball mill media? At the worst I figure there could be some chipping (or even a marble breaking, though that is much less likely in a small mill).

 

In searching for ceramic grinding media, I found that the same companies that produce ceramic grinding/deburring media also sell glass media for grinding purposes. Marbles are certainly tought enough, I'd think - they're hard as hell to break. And heavy-ish

 

What do you guys think?

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Yes they chip and contaminate your BP with glass and anther reason is that they can spark IIRC. Lead is far better IMO and safer.
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I didn't think they would spark, but good to know! I would prefer to avoid the dangers of lead, but it seems like the best combination of price vs performance..

 

I read a thread earlier that someone was having success with coins, maybe i'll just go get $10 worth of nickels :)

 

Can the lead also be used to process aluminum foil flakes into a powder? or is it too soft?

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If you’re worried about the lead just avoid the smoke from the BP as much as possible, lead is too soft to mill metals such as Al and Mg you would need steel media of some kind to dot the job.
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Glass will certainly NOT spark !!

 

Glass powder however may increase the friction sensitivity of your milled composition.

It may also seriously corrode the inside of your ballmill.

 

I have used iron bar cut up and barrel bearing rollers both without accidents, which does not mean you can trust them unconditionally.

Steel (like bearings) certainly has the ability to spark when being struck !!

Soft iron should not have this ability, but keep in mind that it releases Fe2O3 as a catalyst to whatever composition you are milling, which is actually a good thing for stuff like BP :P

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Unless you have quartz crystal marbles, I don't think you'll have a problem with sparking. The glass marble sparking thing I feel came from some uninformed person in a science class. There is a class of crystals known as piezocrystals. When heated they can generate an electric potential. Mechanical energy can also generate the electrical potential, of which quartz is very good at it.

 

Someone was sitting in class and goes, "hey, quartz can spark, and glass is kinda like quartz, so glass can spark too!" The fact of the matter is quartz and glass are two different animals. It also must have a relatively ordered structure for the piezo electric effect to work. Glass is an amorphous solid(or liquid depending on who you ask).

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Glass will certainly NOT spark !!

Hmm, I read it somewhere that it has the potential to spark, oh well bad info I guess.

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  • 2 years later...

BUMP!

 

I read somewhere that glass can spark but i didnt believe it hence its.... glass. Had been using marbles anyway this confirms what I though.

 

 

I have been using marbles in my homemeade low speed milland they work GREAT! I make top notch BP in 7-8 hours.

I supose contamination would occur at a higher RPM since in my mil they roll around and in a *real* mill thay would be jumping a bit.

 

Anyway thanks APC I feel safer about milling again.

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I'm not sure if glass marbles spark, but I'm sure they break into small pieces and your composition gets contaminated with glass.

 

I got a question too. I found a good looking cheap container, very suitable for my ball mill. I bought it, but back home I found out that it's made from iron, or steel, because it had iron oxide traces inside. Knowing that I'm using lead/antimony media, would the iron container ruin my safety ?

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I'm still torn on this matter, depite my post a few years ago. Read up on the piezoelectric effect. Glass has the possibility to spark. Just because in one isolated test you couldn't get it to spark, or at least not notice it, doesn't mean it can't happen. There are piezoelectric glasses, but I don't know what is special about them.
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..... There are piezoelectric glasses, but I don't know what is special about them.

 

They give you X-ray vision, so you can stare at your Asian lab assistant's nice hooters test tubes. :rolleyes:

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They actually work in reverse unfortunately. The piezoelectric effect is an electrical current being generated from a material when it is stressed. This is how the "piezo" lighters work. They work in reverse too. You can put electricity into these materials, and they will deform and become mishapen. As such, you can run electricity into these special glasses, and they will become frosted. Think clear cubicles that can become more private, or curtain-less windows I've seen something like this on TV, probably the science channel. I read something about making self-adjusting sunglasses like this too.
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Well THAT sure spoiled a perfectly good fantasy....... :D

 

 

 

But now I know what you mean. I've seen something like that on the Science or Discovery channel. They were working with pieces that were MUCH larger than "glasses-sized", and were researching industrial applications for "intelligent surfacing" or some such. They were putting electricity "into" the material, so I think it was piezoelectric.

 

I also seem to remember them saying that research is also going to the other extreme in size, with possible uses in things like surgical stents.

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I'm not sure, but I think I have read somewhere, that glass does/can spark, I think someone proved it at a PGI event or something?

 

Just letting you know, what I know.

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I got a question too. I found a good looking cheap container, very suitable for my ball mill. I bought it, but back home I found out that it's made from iron, or steel, because it had iron oxide traces inside. Knowing that I'm using lead/antimony media, would the iron container ruin my safety ?

 

Can someone please answer to my question ? :rolleyes:

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In my oppinon it should be safe assuming you don't have anything else but the non-sparking media and your BP. That means no contaminations like sand grains etc.

 

Still, the KNO3 would have a corrosive effect on the container, and should the beast go off (it can happen with anykind of media, eventually) you don't want to be close to that thing.

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Well thanks guys, i gues ill be buying some Alimna media before the 4th.
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What's alimna? Do you mean alumina? If so, unless you get the specially designed stuff from Coors-tek, it can still spark. This has been legitimately documented. The stuff from the ceramic place in Texas is not this special stuff, and frankly I kind of have my doubts about the stuff from hobbyfireworks. Even Dave Sleeters stuff is questionable. There is some controversy as to whether or not the spark contains enough energy to ignite BP. It's fine for single chems though.
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Damnit !

 

I was just about to get some :angry: <_<

I guess ill go to my friends uncle who has a bunch of 3/8 1/2 " dowels [aluminum & brass]

Or ill use some nickels like Ned said on Skylighter.

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  • 2 months later...
A bit off topic, but how well does lead work for milling media, assuming I do not add antimony in the lead? If used should I wear a dust mask whenever I open my bp jar in case of lead dust (poisoning), orwhat precautions shold I take? Above it said to avoid the smoke...
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The unalloyed lead is way too soft. Without antimony, you'll be losing over an ounce of lead into every batch of powder you mill.
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I was considering melting down tire weights, but now I wonder if they would be to soft? I wonder if they are alloyed? Anyone know, or has anyone done this with good results?
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I've been using melted tire weights and thats why I am asking. The bp worked good, I'll run a batch and check the weight of the lead afterward to see if I'm losing any.
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