55 replies to this topic

[BigBang]

Sasman, i tend to agree with you. I know of a few people, including myself, who have tried to get Al down to 600-700mesh using a home mill, but havnt even got close. Having said that, BigG, (who generally knows his stuff), said it IS possible to mill down to 600-700mesh using a home mill. I assume he has tried this and succeded.

I would have thought you'd need very heavy media in a large drum to achieve this.





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[BigG]

Sasman, i tend to agree with you. I know of a few people, including myself, who have tried to get Al down to 600-700mesh using a home mill, but havnt even got close. Having said that, BigG, (who generally knows his stuff), said it IS possible to mill down to 600-700mesh using a home mill. I assume he has tried this and succeded.

I would have thought you'd need very heavy media in a large drum to achieve this.
.

Okay ? lets quantify that.

a) I agree about what was said about rec.pyro ? but that?s not the subject of this thread.
Largely the American community ? a community that at the moment is not ?chemical hungry?, supports Rec.pyro. As such, the reason for people across the pound to make there own 600 mesh is virtually non-existence.
c) I think many members underestimate the difficulty of testing for 600 mesh in a amateur lab. If you can get your hand on a 600 mesh screen, you will discover that the mare handling of the screen can cause bents and distortions that will create holes as big as 200 mesh easily. Hence why it is difficult to give a conclusive answer.
d) I myself seen a 200mesh aluminium reduced to 600 by a club member in the USA. This was done in minute quantities, using a ball mill with a jar of 4 inch. The result was tested in ?real? lab, and some reduced particles which were even smaller then that. This is a LONG process ? and the separation of the 600mesh items from the rest is close to impossible on a home scale.
e) I would not recommend members to try to obtain flash type aluminium by home production. In fact, I would not recommend dealing with flash at all. Everyone knows my opinion on the matter.

[alany]

Well I don't have a microscope of sufficent resolution to check the product of my experiments, but I can say that I have made "good enough" Magnesium, Magnalium, and Aluminium from coarse starting material in a 4" mill jar with commercial lapidary "deburring" Alumina media. A week or more is what I required. The yields weren't fantastic because of the relatively small scale of the operation, but I am sure I could scale it up to pound-per-week levels if I needed to.

Magnalium is by *far* the easiest stuff to mill, and it is much more useful than Magnesium, and IMO Aluminium too. It works just fine in flash if that's what you want it for. You can almost get it fine enough for flash with just hand tools.

For the Magnesium I started with *very* coarse turnings off eBay. The Magnalium was reduced to -10 mesh before milling for best efficiency. The Aluminium was coarse swarf and shavings from Aluminium cutting. I suspect my metal powders are slightly contaminated by the Alumina media wearing, but the wear hasn't been significant yet, I am still using my first set of media, the edges are perhaps a little less sharp than they started.

I've never tried milling atomised Aluminium for a significant period of time, I might try that next week.

[Richard H]

I shall have to try this. My own experiments with milling aluminium have been very successful as many here will know. If I can reduce aluminium foil to 120-200 mesh in a week, I can probably get it down finer still.

[StarScream]

I shall have to try this. My own experiments with milling aluminium have been very successful as many here will know. If I can reduce aluminium foil to 120-200 mesh in a week, I can probably get it down finer still.

Richard H: I'm really interested to try milling some aluminum foil as well. Do you just rip the foil into small pieces then throw them in the mill? I know some guys run the foil and some water through a blender first, but I wouldn't know if it helps as I have not tried. Also, are you using your brass milling media for this? Is there any risk of using the same media for aluminum and then BP if the media is washed thoroughly between milling sessions?

Please tell us how it is done 'ol wise one!

[Richard H]

Interesting questions, which I'll attempt to answer.

Firstly about the foil. I actually spent several hours cutting foil roughly with scissors into 1cm ish chunks. In future I would be tempted to use a paper shredder or blender to cut the foil up.

For media I did indeed use the brass media. Now a word about contamination. In practice it is best to have seperate jars and sets of media for different groups of chemicals. e.g. a jar and media for blackpowder or it's constituents only, a jar and media for oxidisers, a jar and media for fuels, and then a jar and media for metal powders.

Not cheap, but it eliminates any contamination.

[Phoenix]

I use a blender to shred foil. I crumple sheets of it into fist sized balls before putting it in. It quickly reduces the foil to a sort of twisted, mashed granular form. Be aware that doing this bluntens the blade, so it is helpful if you can remove it to sharpen.

I have also started batches with foil torn into pieces (about 4 or 5cm square). Since the design of the mill and media was very different then, I can't say what difference it made, but I doubt it was too significant.

BTW: I shedded the Al dry - no water, or, as I have also seen referred to, salt. the aim was just to "chop" it, rather than finely grind it.

I have used flint pebbles and large steel nuts to mill aluminium, with effectiveness increasing in that order. There was a silver colour on the jar and media after I milled the Al with it, but I just milled some clay afterwards, before washing it as usual, and this seemed to get rid of most of the colour.

Edited by Phoenix, 19 February 2005 - 09:12 PM.

[StarScream]

Now a word about contamination. In practice it is best to have seperate jars and sets of media for different groups of chemicals. e.g. a jar and media for blackpowder or it's constituents only, a jar and media for oxidisers, a jar and media for fuels, and then a jar and media for metal powders.

Not cheap, but it eliminates any contamination.

I couldn't agree more. I already use separate milling jars for EVERYTHING I mill. I currently only have one set of brass milling media, which I wash really well between milling sessions. I plan to make another set or two of media down the road when I can afford it.

[Andrew]

Okay ? lets quantify that.

a) I agree about what was said about rec.pyro ? but that?s not the subject of this thread.
Largely the American community ? a community that at the moment is not ?chemical hungry?, supports Rec.pyro. As such, the reason for people across the pound to make there own 600 mesh is virtually non-existence.
c) I think many members underestimate the difficulty of testing for 600 mesh in a amateur lab. If you can get your hand on a 600 mesh screen, you will discover that the mare handling of the screen can cause bents and distortions that will create holes as big as 200 mesh easily. Hence why it is difficult to give a conclusive answer.

Just a quick note on mesh, high quality plain weave ss mesh is very strong and holds it shape very well. To make 600# holes to 200# size would require you to break the screen in a way that is visible to the naked eye, and thus easy detection. The biggest problem with 600 mesh or there abouts, is that it is very expensive, in the order of ?200 for a 12" square expensive. The other technicality with mesh sizes is the porosity and the wire size. 600 mesh grades powder very slowly, so there is a tendency to think that the stuff that did not pass is not ?600#, a lot of it will be. The wire size is very significant when you get to this size, although they are very small (the reason it is so expensive) you can only demand so much. A 600# screen will pass powder of at least 1400grit. Maybe not too quick.

The best way to test down to that mesh size on a budget is using a microscope, a visual statistical analysis is as good as any. A cheap jippo salter science scope is even good enough, anything with a magnification over 500 is good enough.

Edited by Andrew, 03 March 2005 - 11:08 AM.

[Salut151]

Hello,
I saw on another forum a method of making Al powder with a food blender. It consist of taking aluminium foil, cutting it (1cm x 1cm) and putting it in the blender with salt. But after I grinded all the aluminium, I've puted water to disolve salt but the water turned gray and I got only few aluminium powder. I eared that I could put a non-oxiding solvant like ethanol (to remplace salt) but I don't know much about it.
Could some help me to improve this method ?
Thanks

Edited by Salut151, 21 August 2005 - 01:33 AM.

[italteen3]

Salut151 there is a search feature on this forum for a reason... This exact topic has been discussed before with much detail. And what use for the aluminum might you desire?

EDIT5 Minutes worth of searching, most of your questions should be answered in there.

http://www.ukrocketr...497

Edited by italteen3, 21 August 2005 - 02:46 AM.

[Salut151]

Oh yah sorry I forgot to search. I Promise you that I will search next time
Thanks

Salut151 there is a search feature on this forum for a reason...  This exact topic has been discussed before with much detail.  And what use for the aluminum might you desire?

EDIT5 Minutes worth of searching, most of your questions should be answered in there.

http://www.ukrocketr...497

[Salut151]

I would like to know if I can put my Mg bar in my ball mill with many lead balls to make Mg powder ? Do I must put something else ?
thanks

[completebeginner]

i dont think a bar in a ball mill would work what i do for aluminum and zinc powder is grind it with a sandpaper covered drum on a hand drill. after i get a decent amount of powder that isnt all that fine i ball mill it for about 4 hours and after its finer than flour

[chris17]

I found this interesting page on grinding metals with a grinding machine. Those machines have similar construction to a ball mill and I suppose it wouldn't be too hard to build one.

http://members.shaw....er/grinder.html

Edited by chris17, 17 October 2005 - 03:59 PM.