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Sonny Jim
October 1st, 2003, 01:56 PM
Ive just came up with a really effective way of producing good fine aluminium powder with totally minimum effort.

Here's what you do.

Get a food blender, you dont even need a mill attatchment. Also have a jug of water standing by.

Now, put enough soluble material (I use NaCl) into the blender and turn it on. You want enough so the blender doesnt throw everything around, but instead sets up a kind of cycle where the stuff comes up from the bottom and gets replaced by the stuff on top, so it plunges down the middle of the blender like a sinkhole.

Now, get some aluminium foil, and rip it into smallish pieces, about 1-2" square roughly. Place these into the blender, and manually shake it a bit to mix the foil in with the NaCl or whatever. Now, turn on the blender and use it in short bursts so as not to overheat it.

The foil gets finely ground up and has no escape from the blades as there is salt all around it!

Now, add the ground up mixture to water, the salt dissolves, and now filter the Al powder and there you go. Hope this helps people out a bit. Later.

Mr Cool
October 1st, 2003, 04:46 PM
Sounds interesting... I'm going to knock up a little batch and see what it's like!

Tuatara
October 1st, 2003, 06:25 PM
Sounds like a good scheme to prevent a pyrophoric explosion too - displacing the air with an inert solid ! Holy flashpowder , Batman! I'm going to have to try this too.

100 Brownie points for Sonny Jim.

Skean Dhu
October 2nd, 2003, 12:23 AM
having just tried this I am rather impressed and distraught(sp?) at the same time. impressed at such good results from a mediocre food processor that I "Ruined" while making charcaol powder(or so my mom says) and distraught that someone(mostly me) hadn't thought of something so simple yet effective before. You don't happen to have a screen or something to measure the particle size of your milled Al powder do you? cause that would be great to get a general idea of the size one could get with such primative methods.
having used salt I no now the location of every minor abrasion on my fingers,

Hang-Man
October 2nd, 2003, 04:54 PM
Clever.......If you follow this up with some ball milling it should yeild even better results.. I should hollow out some pennies and make some copper powder the same way.

blindreeper
October 2nd, 2003, 09:36 PM
Don't bother getting the copper from pennies, rather make a strong copper sulfate solution and stick a bit of aluminium in there. Not foil because it gets messy. After bout 1 hour the aluminium is thick with copper powder that just scrapes off.

green beret
October 3rd, 2003, 01:07 AM
This is very good, I just tried it and it works well, I didnt make heaps but still, its better than buying crappy Al powder thats only good for thermite. Has anyone used this in flash yet? I am going to try it with KN03 or KMN04/S.

Well Done sonny jim.:)

nbk2000
October 3rd, 2003, 01:37 AM
I wonder if you could use the curved bottom of aluminum soda cans as forms in an electroplating circuit to deposit copper onto it to form a small scale EFP platter?

A-BOMB
October 3rd, 2003, 11:21 AM
I use a similar thing to make AL powder, I made a three part AL maker, the first part is basicly a big large industrial blender, some wire brushes that you use for taking off paint with a hand drill and some smallish hand brushes. I took some of the and brushes and epoxied them to the inside of the blender bottle and then welded the drill brushes shafts together so they were stacked then I threaded the last shaft on the bottom brush and tapped the top of the blade cutters. Then I fitted it all together so the wires from the brushes were fitted together like the compresser blades of a jet engine. Lastly I took a 1" copper end cap and drilled a hole in it on the corner and brazed a real small brass pipe into it and then drilled a hole in the side of the blender bottle and in the side of the bushing that the shaft for the blades was connected to so I could fill the end cap with oil and it would flow through the pipe to the bushing to keep it oiled so I could have the unit running longer. Without haveing to stop it and open it up to clean out the AL and oil out of the bushing. And the last part is pretty simple I take a pair of hedge clippers and cut a 75 yard roll of AL foil into about 8 1.5" little roll that I put onto a feeder that I put on the top to slowly feed in the AL foil into the brushes were it would get tore into hundreds of little pieces then drop down into the blade were it would circulate around not beable to go up because of the brushes and would get turned into very fine powder. Sorry if this was a little run-on. I'll see if I can find a pic of the unit before the motor burnt out.

spring
October 12th, 2003, 10:12 PM
Would it be even possible for the Al to become pyrophoric when it will only be "ground up" so to speak for a very short peroid of time? I mean, its not a pyrophoric alloy, and I could imagine it becoming pyrophoric when spending days in a ball mill with no occasional opening of the cylinder, but maybe I am wrong.

vulture
October 13th, 2003, 04:19 PM
Yes, it can become pyrophoric.

The reason why Al powders gets pyrophoric in a closed grinder/mill is because you are constantly scratching the surface, exposing fresh Al to air, which will immediatly oxidizes to Al2O3, forming a protective layer. However, when using larger amounts in a small enclosed space, the oxygen will be used up after some time and more and more pure Al will accumulate on the surface. Because there's so much Al exposed, the energy liberated by those small oxidations can be enough to ignite the whole batch, once you expose it to air.

THe_rEaL_dEaL
November 9th, 2003, 07:11 AM
When you say a blender are you talking of the slender upright device with the small roatating blade/fingers at the bottom? They get commonly used for making smoothies and milkshakes.

Is this the device
If this works as well as you say...
It sounds too good to be true
this is awesome if it works.

Alfoil in australia is commonly alloyed with tin isnt it?

blindreeper
November 10th, 2003, 02:02 AM
Thats a milkshake maker :p A blender is the thing that you can grind up vertables and is quite low and fat with a removable blade system in them.

Tuatara
November 10th, 2003, 03:45 AM
Over here we use the term 'blender' for the tall upright thingy with little bitty blades, and 'Food Processor' or 'Kitchen whizz' (kind of like 'Xerox' :rolleyes: ) for the short fat thingy with the swappable blades.

Bert
November 10th, 2003, 10:35 AM
Aluminum foil for kitchen use is generaly very pure Al.

chokingvictim78
November 10th, 2003, 09:25 PM
Ah, that clears it up. I tried it with a milkshake maker (we call them blenders, around here at least) and thought I was just retarded or something, because I ended up with large, chunky bits of Al, like you would get by cutting it up a bunch with a big pair of shears, no matter how long I ran it. I'll have to go find one at a pawn shop or something, and get some salt and foil and try it again.

Tuatara
November 11th, 2003, 12:55 AM
I'm considering trying this with linseed oil instead of salt. That way I'd end up with oil coated Al powder. I think the oil should be thick enough to provide resistance the way the salt does. I've just tried with salt and ended up with 'air-float' salt going everywhere :mad: . Not the sort of thing I want all over my steel tools.

Anyone care to comment on the linseed oil idea before I waste all my raw oil, or Al foil?

Microtek
November 11th, 2003, 05:52 AM
I know what you mean about the air float NaCl; the same thing happened when I did it. I solved it by covering the lid with kitchen film, but it would be preferable not to have to deal with it.
I think it is impossible to predict how well oil will do as a substitute, but I think the idea is good if it works. It will mean that the powdered Al is not oxidized by the water when dissolving the salt, as the residual oil would be removed with acetone or alcohol. Also, there would be better circulation or the Al I think. It would probably be very slow to filter off the Al when done, unless you could apply suction.
You could also use a mixture of solid and liquid if straight oil is not good enough. Please share the results if you decide to give it a try.

Edit:

Ok, I tried it myself, and it seems to be very workable. Here is what I did:
An amount of rapeseed oil sufficient to reach ca. 5 cm above the blades was poured into the blender ( BTW, I'm using one of the tall slender ones ) and as much Al foil was put in as would fit without cramming it together. The blender was run for just long enough to pull the Al under, and reduce the size of the pieces somewhat. This cycle of adding foil and blending to make room for more was continued until the liquid thickened appreciably due to the large amount of solid present. I believe that as much foil as the operator has patience for should be added, as the Al will act as its own grinding agent filling the role of NaCl in the original concept. Thus, the higher the solids loading the smaller the particle size can get. Also, I don't think more oil is needed than to just cover the blades.
Once enough foil had been added, the actual grinding cycle was commenced by blending for 3 min and letting the motor cool for a few minutes. The cooling cycle also allowed me to see how fine the powder had become as it got more and more compact and accordingly took up less and less space after settling.
I haven't finished this cycle yet, so I can't say just how fine it can become, but I think a quite high mesh can be achieved.

Jacks Complete
November 11th, 2003, 09:10 PM
Excellent! I was wondering where I was going to get some more Al powder from. This will also give me a use for the not-so-old blender I liberated from the other half.

Nice one! :)

To deal with the air-float problem, could you not just take the blender jug outside and then add a bit of water? That would damp it down quite a lot quite easily, and if it didn't all the salt goes outside. Or would the salty water react with the Al?

Could you use something like Bicarb of soda instead? It is also water soluble but not corrosive.

Oil coating everything just seems like a real hassle...

Bert
November 11th, 2003, 09:46 PM
Could you use something like Bicarb of soda instead? It is also water soluble but not corrosive.

Aluminum is badly coroded by bases, even fairly mild ones. Using baking soda for making yellow glitter stars with Al causes the Al to deteriorate, wouldn't expect putting very fine flake Al in a strong solution of it would be a good thing.

The oil mix sounds like the paste Al sold to paint makers. You'd have to do a solvent extraction to use it for flash powder- I suppose it could go straight into am ammonal type HE though.

Microtek
November 12th, 2003, 07:27 AM
I t does indeed require some washing with a solvent for vegetable oil, such as gasoline, acetone, xylene, toluene, etc. It is not that much of a problem as ca. 90 % of the oil can be removed by filtration. This can then be used with the next batch. BTW, a certain amount of the powder passes through the coffee filter which must mean that it is quite fine.
It would be best if some liquid could be found which is non-oxidizing and reasonably volatile, while also being non-flammable and viscous. Now, volatile and viscous doesn't go together in any solvent I know of, but if the viscousity is supplied by increasing the solids load, then gasoline might be a pretty good choice ( even though it is not particularly non-flammable ). Of course there is also the problem of plastic parts in the blender not being resistant to many organic solvents, but if using a plastic blender, maybe alcohol could be used instead.

Tuatara
November 14th, 2003, 04:16 AM
Just finished drying the roll of Al foil I ground up, using linseed oil. Result looks good, after washing with white spirit (hexane). 90% of the oil was removed simply by allowing the Al powder to settle out, then decanting. I've left the decanted oil sitting in a 500ml measuring cylinder, as there is quite a bit of Al dust still suspended in it. I've done the same with the white spirit used for washing the bulk powder. It will be interesting to examine the proportions of the various powder sizes I have obtained. I used a paper towel for a filter - some extremely fine dust went through.

I didn't get this microscopic dust with the salt / water wash - just grey gunk coagulating in the salt solution.

Summarising my impressions of the two methods:
Salt + water pros: is very cheap, no nasty volatile solvents required.
Cons: produces air-float salt leaking out of every gap in the blender, can't see the progress of the grinding, Al fines are being oxidised into uselessness

Oil pros: Can monitor grind progress visually, can recycle 90% oil at least, oil prevents oxidation
cons: organic solvent required for wash, consumables are more expensive than salt

Microtek
November 14th, 2003, 05:55 AM
It has been three days since I filtered my batch, and even though the filtrate has been left undisturbed since then, the Al powder that passed through the filter hasn't settled yet. The liquid just looks as if ink was added.

Tuatara: I think I will try using ethanol instead of oil. If this works, it will be possible to use a much finer filter because of the low viscousity and surface tension relative to oil. And once filtered, the alcohol can just be allowed to slowly evaporate to leave completely pure Al powder.
It is probably advisable to restrict the evaporation of the ethanol in order to avoid fast oxidation.

Bert
November 14th, 2003, 10:43 AM
Add a VERY small ammount of stearine to the solvent if you're worried about the Al oxidizing.
Scrape a bit of the outside coating wax off of a dinner candle if you can't buy stearine-
It will phlegmatize the Al for flash use, but it won't go "poof" on you either...

Tuatara
November 15th, 2003, 02:29 AM
I found the white spirit was fluid enough that I was able to use a sheet of blank newsprint for a filter. None of the Al dust went through, and the paper now looks like it has been painted with a high quality silver paint. I'd say it took around 4-6 hours for 200ml of white spirit to pass through the newsprint.

You could heat the oil before filtering, but that seems like too much effort to me.

I've also been thinking that paper vacuum cleaner bags might provide a good source of filter paper, being somewhat thicker than coffee filters, yet obviously porous enough to pull air through. Also the large size of vac bags would allow the use of a large filter funnel - so you could dump a litre of liquid in then go to bed, leaving the filter to work overnight.

Microtek
November 15th, 2003, 08:06 AM
I have just ground up 70 grams of Al foil using ethanol instead of vegetable oil. It works at least as well, with the only problem being that it takes a little more time for the blades to drag the foil down as there was not nearly as much circulation when blending as with oil. This could have been due to using too little ethanol; when I added more after having added all the Al, it started circulating much better.
I have ground the mix in 2-3 minute runs for a total of ca. 30 minutes, and the powder is becoming very very fine. As with the oil mediated batch, there is a size distribution, but the most coarse powder is less than 0.1 mm in the largest dimension ( the foil is 0.011 mm thick ) and the finest powder is completely black and individual grains are invisible to the eye.

Jacks Complete
November 15th, 2003, 06:06 PM
In my earlier post, I mentioned using Bi-carb. Now, Bert said that there would be problems using any base, and that is probably true. However, my point was, couldn't you use something that was cheap, available and water soluble? Bi-carb was just my first guess.

As another thought, using remote switching, couldn't you use a strong oxidiser, like AN or KNO3? The ANAL mix needs a pretty strong blasting cap to set it off, and switching the blender remotely would reduce the risk to nothing for a trial run...

Before anyone flames this idea, the obvious way to do it is to get a 12v car battery, an inverter for £20, and an extension. Now take your ingredients to where you would do your test of the finished product, set it up, stand well back, and see what happens!

I figure it would be safe, so then after it has mixed well, you pour it out, stick in a cap, and set it off.

If it goes off early, we then know what not to do, and all you are down is a blender.

Might want an earth bank between you and those blades, though!

Any thoughts? This way you couldn't get done for having any explosive, either!

PanMaster
November 15th, 2003, 07:45 PM
what kind of blender could make Al so fine it goes black? Microtek, is it as good as dark Al?
surely the Al would get to a certain size and then the blades would simply push it around without any grinding action as the mass of the indiviudal pieces of Al would not provide enough contact force for the blades to cut it.

Bert
November 15th, 2003, 09:08 PM
Jack's complete lack of a blender-

Jack, if you put an oxidizer and a fine metal powder together in a high speed blender, you will be short a blender quite quickly. By all means try, but only in a place where it won't matter...

Tuatara
November 16th, 2003, 04:32 AM
PanMaster: Obviously any kind of blender or food processor can do this ultra fine powder, as thats what both Microtek (blender) and myself (food processor) seem to have obtained. It may be that at that size the blades are no longer cutting, but creating sufficient shear in the fluid around the blade that the foil is torn apart. I must admit to being rather surprised at finding such fine powder in the resulting mix, especially since I gave mine only 10mins of running time.

Jack : Stop. Think. Which is cheaper - bicarb or common salt? Heck if you're really skint you could grab a bucket of seawater and dry it. As for blending with an oxidiser - I'm sure I've seen stories of Al being blended with nothing but air, then *BAM* no blender, because the Al went pyrophoric.

PanMaster
November 16th, 2003, 08:21 AM
so it uses liquid to do the work, what kind of organic solvent, or just water?
so far i found with a mixture of some water and salt the foil just gets pushed around, cut here and there, and a lot of mess, there is also an overheating problem...:rolleyes:

blindreeper
November 16th, 2003, 08:35 AM
PanMaster, Microtek posted that he used ethanol instead of oil. Does that answer this question?
so it uses liquid to do the work, what kind of organic solvent, or just water?
Water would react with the Al I think as it gets finer and finer.
surely the Al would get to a certain size and then the blades would simply push it around without any grinding action as the mass of the indiviudal pieces of Al would not provide enough contact force for the blades to cut it.
You can't have an explaination for everything it just works :p

xyz
November 17th, 2003, 06:39 AM
Panmaster, The blades are moving fast enough that things will be ground pretty fine. To get an idea, ask anyone who has ever used a coffee grinder to powder AN or KNO3.

Bert
November 17th, 2003, 11:17 AM
If there is enough turbulence, impact with the blades is not the only mechanism at work. Ever hear of air milling? (http://daega.co.kr/_html/goods/tam.php)

Microtek
November 17th, 2003, 12:38 PM
In my limited experience in the art of grinding, there needs to be a certain amount of Al in the blender along with the liquid. Here follows my attempt at a plausible explanation:

At first, when only a few strips of Al foil has been added to the blender, the primary grinding action comes from the blades. They are able to cut the foil into quite small particles because the liquid acts as a backing that prevents the foil from being pushed back by the blades. This can reduce the particles size to a point ( perhaps a little less than a millimeter ).
Once enough foil has been added and the grinding commences in earnest, the particle size drops below the level where the force excerted by the fluid on the individual pieces of foil is not great enough to cause the Al to be cut, so the pieces are simply pushed away.
However, because there are such a high density of Al pieces in the fluid, they grind each other due to the rapid agitation of the mix, rather like the way you grind coarse salt between your fingers; it is very hard to grind single granules of salt because soft skin isn't capable of applying enough strain to them, but if two or three granules are rubbed against each other, they are easily ground.
A consequence of explaining the phenomenon with this model is that the viscousity of the liquid medium would be of little or no importance to the minimum grain size that can be achieved. This was seen to be the case when I tested the method with ethanol.

Jacks Complete
November 17th, 2003, 07:40 PM
Bert, Tuatara,

That was my point! I thought my post was clear enough?

You take your cheepo car-boot sale blender, add the ingredients, and set it up, then blow the lot to kingdom come. No problems with detonation with a cap, no primary, nothing, just an intimate mix of ~1kg of ANAL going pop! That is a bloody big bang!

Don't forget, the aluminium isn't finely divided at first, and the prill AN needs no preparation beforehand either. If the cops look, they see something suss, but no explosive, nothing they can even cofiscate legally! Simple and elegant, espcially if you can get an old blender for £5 from a sale.

And if it doesn't go off, you can be quite sure it will be safe to go back to after ten minutes with no power.

Bert
November 17th, 2003, 10:36 PM
Jack, it would most likely just catch fire/deflagrate. No hefty shock to get it to detonate- Just an ignition source. Flashpowder type burn at best would be my prediction. Go ahead if you've got the space and a spare blender, I could allways be wrong...

arm
November 25th, 2003, 11:01 AM
Has a anyone tested a batch of powder made by this method to ascertain its quality? If its good I may give it a shot. I usually manufacture my Aluminium powder via the good old Ball Milling method which produces good powder but can take over a week of continuous milling to finish.

If this method works well it could be used to eliminate milling or reduce the time significantly.

Mendeleev
December 12th, 2003, 09:00 PM
I tried this method today, I added about equal volumes of salt and AL foil which was chopped into 1 by 1 cm squares, with disastrous results. After letting it grind for 30 minutes. I dissolved everything in water and filtered. I had pretty big Al prills leftover, about 1-2 mm in diameter :(, and the water turned black meaining some of the stuff was too fine to filter. Where have I gone wrong :confused:?

metal dragon
December 12th, 2003, 10:57 PM
Jack’s complete,
If you use AN or KNO3 won’t you just be encouraging the risk of making Al oxide? If you use ethanol or another non-oxidizing liquid you won’t have to worry about making too much Al2O3. Isn’t the goal to make Al powder not Al2O3 powder?

Tuatara
December 13th, 2003, 04:44 AM
I've just found the one problem with linseed oil, and I should have remembered this too. Linseed oil is one of a number of hardening oils - that is they react with oxygen and polymerise or crosslink or something, and go hard. Great for protecting wood - bad for Al powder. I didn't wash mine thoroughly enough, so now its slightly sticky and forms large clumps. :(

charger
December 13th, 2003, 08:22 PM
I'm not sure, but I have heard thet etch-a-sketches are full of aluminium powder. They can be bought dirt cheap used at 2nd hand stores and yard sales all over the place

Mendeleev
December 15th, 2003, 12:33 PM
Well I'll be damned. Etch a sketch eh? Well I'll have to see about that. In the meantime I repeated the procedure, equal volumes of salt and Al foil in a blender for 30 minutes. Same results large Al prills and black water. No powder. Were is my mistake?

Dee
December 17th, 2003, 02:45 PM
According to http://ask.yahoo.com/ask/20000830.html an Etch-a-sketch is filled with a mixture of aluminum powder and plastic beads. Now to hit a thrift shop and begin experimenting.

Zeitgeist
December 22nd, 2003, 07:49 AM
Surely finely divided Al will react with the water using the NaCl method?

3H2O + 2Al --> Al2O3 + 3H2

Even if only to a small degree?

Hang-Man
December 22nd, 2003, 04:37 PM
Yes, it will rust to a degree, but unlike Fe, when Al oxidizes, it forms a protective layer of Al2O3 on the outside, preventing further erosion. Unless the Al is atomized in the blender, which it is most certainly not, there should be no problem. If you're just making flash with it, Al2O3 will work anyway.

Mr Cool
December 23rd, 2003, 10:06 AM
Al2O3 will NOT work in flash!!!

Hang-Man
December 23rd, 2003, 11:00 AM
not if you're using PURE Al2O3, but if theres enough Al to get the rxn going and produce heat then wont the O get displaced? Maby not... the point is don't worry about Al rusting.

Mumble
December 23rd, 2003, 01:17 PM
The Oxygen will not get displaced. Somewhat (>1/4 the surface area or so) oxidised Al will greatly reduce the efficiency of the flash powder. I wouldn't be suprised if it went from flash powder to shooting sparks all over powder. A small amount of oxidation won't really do any noticable damage to the flash, but it's still not something you want. When grinding in water there will undoubtably be some oxidation, but there wont be enough in the short period of time its in there to do any really damage to the quality.

Axt
December 23rd, 2003, 01:29 PM
Yes it will...

Grinding Al for a couple hours (whats a short period of time?) in boiling water will make a lot more Al2O3 then Al, because as the oxide layer forms its ground straight back off. Best use something else such as alcohol as Microtek has done! its cheap enough and easily evaporated from the Al.

YayItGoBoom!
December 24th, 2003, 05:55 PM
Would acetone work just as well as ethanol? I don't have any ethanol, and don't know of any moonshine joints in this neck of the woods either, but acetone is easy as piss to come by.

Hehe, I don't have any white gas either, but acetone would work just as well as a solvent for oil, right? I have about a quarter pound of Al shards from my school's CNC machine (one of the projects involves milling aluminum keychains). One of these days I am going to try and raid the machine shop for Al shavings too.

Axt
December 24th, 2003, 08:41 PM
Acetone is unlikely to be compatible with some plastic bits on the blender, denatured alcohol should really be easier to find.

Mendeleev
December 26th, 2003, 08:38 PM
I sort of finally got the process to work, I used a finer coffee filter and got some aluminum powder, although the water was still black meaning a lot of it gets through. Does anyone know what kind of filters work best. I was wondering if it would be possible to create aluminum powder by melting it then solidifying it. If anyone has experience with this method I would appreciate the help, for it would seem much simpler and shorter, my oxy-MAPP torch vaporizes aluminum in seconds.

Bert
December 26th, 2003, 08:54 PM
Making spherical Aluminum powder by spraying molten Al into an inert gas stream is done industrialy. You are not likely to do it at home, the equipment is too complex and expensive.

Mg/Al alloy 50:50 is easily smelted and very brittle, it's easily ball milled. It's your best bet for a process you could accomplish at home if blenderizing foil isn't doing it for you. Just be careful smelting, ignition temp is very close to melting temp. Inert atmosphere would provide additional safety.

What kind of filters are you using? There are a lot of diferent porosities available. Coffee filters are pretty coarse.

THe_rEaL_dEaL
January 2nd, 2004, 10:01 AM
I can get 96% pure ethanol very cheap.
I was wondering does anyone think the other 4%, most prolly water, would act negatively in Al production?

Microtek
January 2nd, 2004, 06:31 PM
No. I use 93 % denatured ethanol wherein the last 7 % probably consist of methanol, pyridine and other denaturants. I don't think there is any oxidation worth mentioning.

Mumble
January 2nd, 2004, 06:52 PM
Is your ethanol for human comsumption? It will say something like 190 proof on it and it will come from a liquor store if it's for human consumption.If so, I would hope that the last 4% is water. Or is it from the hardware store? It should say methylated spirits or denatured alcohol or something to that effect. It has methanol and water, often times odorants. In any case it should have no negitive effects on the aluminum.

Blackhawk
January 6th, 2004, 05:53 AM
I am going to buy a cheap used blender to make Al powder with as per this thread, and a few thoughts came to my head. Firstly, why would you use salt or bicarb as the solid 'holder substance' if you were to use one at all, I would use sugar as it is unlikely to react with the Al and it can be removed by washing with water and recovered by evapourating the water if you really want to be cheap. Secondly I was a bit iffy about the time needed as you would have to pulse the food processor on and off for around an hour (30min run time 30min rest time in 1min intervals) which could be really boring as you would have to sit next to the blender turning it on and off all the time making it hard to do anything else. Then I saw a timer kit at dick smiths (= radio shack) called the "Pulse Timer" which basically triggered a relay on and off (set by two potentiometers) over and over again (sorry I would link to the website but it isn't there for some reason) I have attatched a picture that shows how the timer would be attatched, but the idea is that it would automatically turn the blender on and off every minute untill you came along and took the power supply away from the timer. It would require very little work to attatch (soldering two wires to the power switch of the blender not including making the timer) and you could even have the wires from the switch leading to a nice clean looking socket in the blenders body where you attatch the timer, this way it could still be used as normal if needed.

Tuatara
January 8th, 2004, 12:44 AM
No.
Otherwise thats the way it would be done commercially, instead of by electrolysing molten alumina / cryolite at some ridiculous temperature.

keith
January 9th, 2004, 09:14 PM
I havent tried this yet but in recently needing AL I think I will. What about a belt sander with a dust collector, a bar of AL, and a bucket. You could get a coffe can full in about an hour.

Blackhawk
January 9th, 2004, 09:21 PM
The problem with using a sanding device like that is that your Al will be contaminated with grit from the sandpaper, you may also have a problem with the decently fine powder blowing everywhere (including your lungs) so the only thing that falls into the coffee jar are the big useless chunks.

Microtek
January 10th, 2004, 12:57 PM
If you dip part of the sanding device into ethanol of some other non-oxidizing fluid, the Al dust will collect in the fluid reservoir. It works just fine, but in my experience it is faster with a blender and Al foil.

schwarttzy
January 18th, 2004, 02:01 AM
Go to NAPA Auto Parts (or any kind of auto store) and ask for AlumAseal. It is used in the raidator to stop leaks. Any ways it is powder aluminum in a need of milling thats all!

Mendeleev
January 21st, 2004, 05:26 PM
I bought some of the alumaseal today at NAPA, and it is an oily brown liquid, but I can see sparkly silver stuff floating inside, which I am guessing is the aluminum, I'm guessing the brown stuff is a solvent of sorts that needs to be evaporated?

Mendeleev
January 22nd, 2004, 09:23 PM
Unable to find an exact sheet of ingredients or MSDS on Alumaseal I decided to do some experimenting in boiling away the solvent to leave theoretically pure aluminum powder. As I poured it into the beaker I had to pore it back and shake up the can because there was a significant amount of sand and not aluminum powder in it. After successfuly pouring it into my beaker I put it on a hot plate which I monitored for ten minutes. Everything seeming fine I went to have a glass of water, and when I came back I noticed a very large plume of white vapors coming out of my beaker. As a precaution I went to fetch some water, and when I got back with the water which was about 25 seconds the damn thing was flaming. I dumped into the beaker a half liter of water and poof an 8 foot fire ball occured 3 feet from where I was standing engulfing me my hotplate, stool, and chair. Luckily I suspected the fire could have been a grease fire and maintained my distance. All I can say is schwartzy you are a fucking asshole newb, who needs to learn to tell people a little more fucking information before you send them off on a death quest. The shit probably has to much sand in it anyway to purify, and now I have a hell of a cleaning job to do on by beaker not to mention clean up to sizzling aluminum powder shrapnel on my porch. I bet you never even used the shit yourself. What a goddamn ass...

atmosphere1
January 26th, 2004, 03:27 AM
My Al-powder is made bij letting steal balls(about 30 ) run over AL-foil with great force (how do you call that in English? walsing mabey? ),together with an organic solvent . To attchieve this i have used 2 round (power lifting) weights . I put the AL foil and the medium on the first weight ,then place the second one on top of it and put an axle trough both weights. On top of the second weights i place even more weight ,about 50 kg . When you rotate the second weight ,the steal balls (between the two weights ) wil get thinner and thinner,and eventually become a very fine powder . or a paste in this case (with the organic solvent ).

An advantage is that there's no heat involved,and your al will be very bright (no oxide)


this is a very short rough explanation , but i hope its enough to give you an idea on how it works.

Spleenman
April 10th, 2004, 02:26 PM
What can I filter this with? Tried doubled up coffee filters, but most of the really fine stuff goes through. I see someone used blank newsprint; I have a lot of old newspapers lying around. Anyone know if there's anything in ink that would corrode Al (Or otherwise make it useless for flash)?

Macaman
April 10th, 2004, 03:14 PM
Clever.......If you follow this up with some ball milling it should yeild even better results.. I should hollow out some pennies and make some copper powder the same way.

Since 1981 pennies have been copper plated zinc. Very little copper in them.

Mendeleev
April 10th, 2004, 06:50 PM
When he said hollow out he probably meant make a small scratch on the copper foil plating, and dump the pennies into hydrochloric acid, which would leave you with a hollow penny. If it was an old penny, there would be not need to hollow it out, and it would be difficult to make it into copper. The foil left behind by the hollowing out is so thin, you could crumple it with your hands to make copper powder.

tmp
April 19th, 2004, 04:30 AM
Aluminum will react with hot water to produce Al2O3 and H2. The finer the
powder the faster it reacts. And boiling hot water with NaCl in it speeds up
this process greatly. For an experiment, I placed some fine(don't know the
mesh) Al powder in cold water. In the course of several days I noticed slow
bubbling coming up from that mix. I will assume this is H2 and not trapped
air. After 2 weeks, I poured off the water and noticed a small amount of a
white substance mixed in with the Al powder. I'm sure this was Al2O3.

I still ball mill my powder using 3/8" steel slingshot ammo and 1/2" steel ball
bearings. I open the ball mill every 2 days to allow some air in it. I'm not
worried about the ultra-thin Al2O3 coating that prevents the powder from
becoming pyrophoric. The next step is to filter the powder through a very
fine fabric that can be found in an arts and crafts store. What doesn't get
through the cloth goes back into the mill. This powder is extremely fine and
will form a dust cloud if dropped a few inches in the air.

The next step is to mix this powder with denatured alcohol. It is then put
through a cut up HEPA filter vacuum cleaner bag rated at .5 to 1 micron.
It helps to have a filtration flask at this point because filtering by gravity is
extremely slow. Again, what won't filter is put back into the mill. The flask
is plugged to allow the filtered powder time to settle out. After settling,
the alcohol is carefully poured off leaving a small layer of aluminum powder,
slightly wet with alcohol. Allow this to dry out and place in an airtight
container.

This procedure requires more patience than any fast method of powder
production and can be quite messy for the novice. The last steps involving
HEPA filtering and settling require the most patience. For me the process is
worth it.

The powder filtered through the fabric is a dark gray color and works well in
flash mixtures. The powder through the HEPA filter is black and will ignite
with a butane lighter on its own. I can't determine the mesh size of either
powder looking at them with a 900x microscope because the particles are too
small. I need a microscope with a higher magnification. BTW, this black
aluminum powder burns easier than the German Dark I bought(expensive !)
for comparison.

Ropik
May 9th, 2004, 06:26 PM
Salt... Oil... Bicarb... Maybe I have different kind of cofee grinder, but I can tear Al foil with it to reasonably small pieces without any additive.
However, there are two kinds of cofee grinders:
1) blade grinder: It grind like small blender.
2) stone grinder: It has grinding wheels("stones") that grind and tear everything.
I have second kind. Maybe majority of people use the first.
I found grinding with stone grinder slower but more sure and the resulting powder is normally finer. In addition my grinder has different particle-size option, so I can grind almost everything.

P.S.: I am just happy because I got grinder few days ago and it class up from mortar, pestle and rolling pin.

kryss
June 5th, 2004, 12:54 PM
I found a patent which describes how to make mixed metal/Lanthanum powders - See no reason why it will not work with ordinary metals:

Dissolve metal Carboxylate eg acetate and reducing agent such as Hydrazine in solvent , and heat to set temperature - metal is reduced and worked up. Probably needs to be done in aninert atmosphere. OK Hydrazines probably hard to get hold of but another solvent soluble reducing agent might work. And your slovent would need to be dry of course.

Bugger
August 20th, 2004, 11:35 PM
I found a patent which describes how to make mixed metal/Lanthanum powders - See no reason why it will not work with ordinary metals:

Dissolve metal Carboxylate eg acetate and reducing agent such as Hydrazine in solvent , and heat to set temperature - metal is reduced and worked up. Probably needs to be done in aninert atmosphere. OK Hydrazines probably hard to get hold of but another solvent soluble reducing agent might work. And your slovent would need to be dry of course.

Rare-earth metals, or mixtures with them, are highly pyrophoric; and their powders are easily inflammable, producing a white heat like Al and Mg powders. This is why they are used for ignition in cigarette lighters. However, the method you gave for obtaining La metal would not work - it is too highly electropositive, being somewhat more electropositive than Al although slightly less so than Mg. As such, the only practical method of obtaining it is by electrolysis of a fused halide.

Bugger

Bugger
August 20th, 2004, 11:43 PM
I found a patent which describes how to make mixed metal/Lanthanum powders - See no reason why it will not work with ordinary metals:
(cut)

BTW Al powder, like Mg powder and thin strips, is a hazardous material when heated in air. It burns with a white heat, giving off much ultraviolet light. This is why it is used in thermite bombs (used as incendiary bombs dropped by bombers) and fireworks.

Bugger

CommonScientist
August 24th, 2004, 03:47 AM
There are plans of an automated Al grinding machine, uses a spring to add pressure to the Al stock, and feeds it into a grinder, which spins in a thin oil bath, adn it has some serious potential.

Doug
August 24th, 2004, 04:09 AM
Has anyone tried using iso-propyl-alcohol (IPA) with the AL in the blender, or indeed does anyone know any reason why it wouldn't work?

I have several litres of the stuff for general electronic cleaning use, it's fairly cheap, easy to get hold of in 1 litre tins, and as it's around 99.7% alcohol it also evaporates pretty damn quick.

I'm afraid I'm not really up to speed on whether the other 0.3% would have any kind of negative effect though...

tmp
August 24th, 2004, 03:24 PM
Doug, it shouldn't be a problem. Even mixed with water, I've found that Al
powder takes time(unless it's boiling) to react with the water. I wouldn't
worry about that 0.3 % although at the purity you described I'd be more
worried about a fire if any of that alcohol found it's way out of the blender,
vaporized, and was ignited by any stray sparks from the motor brushes.
I use denatured alcohol to put sub-micron Al powder into suspension and then
run it through a centrifuge. I get highly reactive powder that way.

JimmyJones
August 30th, 2004, 05:21 PM
Wow this really is an easy way to make Aluminium powder. I just tried it and it works great.

Rocket-Boy
September 26th, 2004, 10:59 PM
dude, AL with oil on it will be fine and easy to filter, just get a very fine collender (strainer, kitchen thingy, check with your other half.) and pour the oil (that has AL in it) through, and to rinse the AL, use water, i have tryed this to great success, though i have no means of mesureing the mesh, it it very very fine, like very fine dust in the wind.

to dry it, just place it in the sun. :)

Another, wierd place to find pure AL, is laptop screens. Behind the LCD screen is a sheet of PURE Al paper, and is very brittle. :) , sooo, if you have an old laptop that you dont want, have fun with that :) .

one of my friends suggested just using a magnet for the AL or copper while reading previous posts, but there is no iron in Al or copper, so hes an idiot and that wont work for anyone else who is about tot try to waste there time with that.

tmp
October 9th, 2004, 11:03 PM
More often than not, it's a matter of what happens to be available or
affordable to you. I've used a blender, sander, file, bench grinder, and
what I like most of all - ball mill ! IMHO, the ball mill, like my Lortone FD-12
rock tumbler, with milling media does the best job even if it is slower. The
rub is the price. If that's not a problem for you I suggest you go with it !

Dimroth
October 10th, 2004, 11:15 AM
Be careful when using volatile solvents like ethanol and especially isopropyl alcohol. The blender will greatly increase the evaporation, also, air might get mixed into the fluid. One spark and... :eek:

nbk2000
October 11th, 2004, 12:31 PM
We have two large threads about the same thing in two different places, so I've put them in the same place, with the same name.

I didn't merge them, as that'd disrupt the continuity of the discussion, but only thread #2 will remain open for further posting on this topic.