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Posted

I bought a couple lbs of Magalum 50/50 from Skylighter. It's shipped with half the weight being "turnings", chips really. They will credit you like 7 bux/Lb. on another order of it if you ship the chips back.

 

My question... I have a ball mill, can I just reduce it myself? I have only lead media, I'm assuming I'd need a batch of ceramic? If so...I guess I'll ship it back as opposed to another $50 or more in ceramic media. Then again, that would allow me to do powdered AL too...Hmm any points/advice?

Posted

IIRC the turnings are plain Mg.

 

For reducing metals you want something really hard and plenty heavy... like 3/4" chrome steel balls.

Posted
Skylighter now sells it with magnalium not magnesium turnings not sure how to reduce. It might be a pain in the ass but its possible the best way would be to melt all the turnings back together and break them up.
Posted

The turnings are magnesium - you can't get turnings from 50/50 MgAl, it's too brittle.

 

One option would be to melt the Mg turnings with some aluminum to make more MgAl. It's not all that hard, or expensive, and breaking it up after is easy. I use a meat grinder to get a nice range of meshes which can then be coffee milled.

Posted
and breaking it up after is easy. I use a meat grinder to get a nice range of meshes which can then be coffee milled.

Wasn't someone just saying they blew a breaker and other assorted nasty effects coffee-milling metals?

 

Can the melting be done with a propane torch? Or, I do have a brazing setup, oxy-Mapp gas.

Posted
The turnings are magnesium - you can't get turnings from 50/50 MgAl, it's too brittle.

NOTE: Each container consists of .49 lb. of magnesium-aluminum powder mixed with .51 lb. of magnesium-aluminum turnings. You can remove the turnings with any 20 mesh or finer screen, even a window screen.

 

They aren't really "turnings" they are little pieces like little ovals punched out of a thin metal sheet.

Posted
They aren't really "turnings" they are little pieces like little ovals punched out of a thin metal sheet.

I would describe them as "spall", somthing from a lathe operation that involved a brittle material. Just by the looks anyway.

Posted

Rich: check out the magnalium thread, http://www.apcforum.net/forums/index.php?s...indpost&p=22379

 

Start at that post and read on if you need more info. I suggest melting the Al and stirring the Mg in as it melts. The info's all there, it's very easy to make MgAl.

 

On a side note, if they're listing those turnings/spall/swarf as magnalium, it's probably 95/5 or 5/95. That's pretty much the limit without getting extremely brittle with MgAl alloys.

Posted
Also, as to the breaker et all, I expect some dust got down into the motor and ignited from the brushes sparking, that would definitely cause the MgAl to ignite and the breaker to be tripped. I've personally never seen sparks from grinding MgAl, but that doesn't mean there isn't risk of fire/explosion. Meat grinders are a great way to break up somewhat bigger chunks before grinding, thus reducing the amount of grinding needed.
Posted

Since the filler packing material Mg is essentially commercial byproduct... its probably byproduct from a variety of sources and it probably varies a bit... so your all probably right.

 

Melting down Mg turnings, spal, etc wont work so well without an inert atmosphere since their is so much surface area... Its likely to just ignite when it gets hot enough in the crucible... I'd say that melting down the aluminum, then adding the magnesium to it and trying to get it to sink down in it rather than float and ignite would be the best bet... but... meh... going from ingot/chunk aluminum and ingot/chunk magnesium is obviously less problematic since there isn't so much surface area to react with oxygen.

Posted

Once the aluminum is melted, adding the magnesium turnings isn't a big deal. There is quite a bit more oxide per unit of weight with turnings compared to ingots though, so you have to skim a bit more slag of the melt (or wirebrush it after it's cooled).

 

Tenacles and I made a batch where the magnesium addition was mostly turnings..it worked beautifully.

 

Also, as to the breaker et all, I expect some dust got down into the motor and ignited from the brushes sparking, that would definitely cause the MgAl to ignite and the breaker to be tripped. I've personally never seen sparks from grinding MgAl, but that doesn't mean there isn't risk of fire/explosion. Meat grinders are a great way to break up somewhat bigger chunks before grinding, thus reducing the amount of grinding needed.

 

Yep, that was my thought too. Anther good possibility is that the grinder was used for other materials and wasn't cleaned. I don't think we have the whole story here. ;)

Posted
If the Magnesium is in chip/curl form you could use it up in some BP based comets. See the comet thread.
Posted
If the Magnesium is in chip/curl form you could use it up in some BP based comets. See the comet thread.

It's pretty heavy stuff.. over 20 mesh...since it can be removed from the purchased product with a window scteen.

Posted
yeah, I have 2 pounds of it also, works great in comets and such, even some rockets. Add around 5-10% to a comet or star, I add a little to Ruby Red stars, makes them look really good.
Posted
I don't like that stuff, my window screen doesn't get all of it out and its a pain. I'm going to try -200 mesh MgAl off of ebay next time rather than pay for a pound of metal when I can only use half of it. but I'll try putting some in a rocket or comet and see if I can use it, it's so big I never considered that it's usable without processing
Posted
Karma: get your hands on some magnesium and brew your own. It's as easy as making charcoal. The hardest part is finding a good source of Mg!
  • 2 weeks later...
Posted
Melting down Mg turnings, spal, etc wont work so well without an inert atmosphere since their is so much surface area... Its likely to just ignite when it gets hot enough in the crucible... I'd say that melting down the aluminum, then adding the magnesium to it and trying to get it to sink down in it rather than float and ignite would be the best bet... but... meh... going from ingot/chunk aluminum and ingot/chunk magnesium is obviously less problematic since there isn't so much surface area to react with oxygen.

Have tried 3 times... yer right don't work so well. Out of a total of about 400 grams I got about 10 grams to play with.

 

It IS incredibly brittle... just snaps! But... I guess I'll use the remainder in comets.

 

Thanks Bob

Posted
Did you melt yours in a container, or on a flat surface? When Frank and I melted down my Mg turnings that came with some Mg sweepings from firefox, we didn't have any problem with ignition, but we did use a charcoal chimney, which has proven quite effective. Not critisizing, just curious. When I was making some MgAl using a can + propane torch it didn't work nearly as well as the chimney did.
Posted
Did you melt yours in a container, or on a flat surface? When Frank and I melted down my Mg turnings that came with some Mg sweepings from firefox, we didn't have any problem with ignition, but we did use a charcoal chimney, which has proven quite effective. Not critisizing, just curious. When I was making some MgAl using a can + propane torch it didn't work nearly as well as the chimney did.

Used a can in my charcoal basket from my smoker... basically a Hi-po chimney. 12" X 12" X 12"expanded stainless basket. Melted real well.... too well! But the MG chips just went up in flames as soon as they started to melt. I tried to use a chunk of sheet metal on the top to limit O too. I think too much air is trapped with the chips right at the get-go maybe? Dang that stuff burns BRIGHT LOL!

Posted
Could be.. What I do to put out fires is stir - if you stir the burning part under the surface, it goes out. At least in my experience.. Too bad it didn't work out for you! I am going to try and have some Mg chunks to sell at PGI for reasonable.
  • 1 month later...
Posted
Karma: get your hands on some magnesium and brew your own. It's as easy as making charcoal. The hardest part is finding a good source of Mg!

I've been wanting make MgAl. I’ve made a setup for melting lead in my fire box (casting ball mill media) and tested it on aluminum as well. So i just need a source for the magnesium to do it.

 

I've been told old lawn boy lawn mower decks were cast magnesium. I’ve been meaning to get to the scrap yard to dig for one to try it.

 

I never searched yet, but it would be nice to have a list compiled of sources for (cheep easy to identify) magnesium.

Posted
Not many mower decks are Mg, but if they are green they are liekly to be. I know my local recycling business has a bunch of Mg wheel inserts that came from military vehicles. The put them in the tires so if they go down they can still drive around on the inner Mg rim.
  • 2 months later...
Posted

In the UK magnesium ingots are sold in plumbers merchants for use as sacrificial anodes for some heating systems. Buy the magnesium pure for the metal price rather than the unspecified alloy for yard price.

 

Someone in the UK is thinking about a batch of 75Mg 25Al magnalium as the reason for some spontaneous ignitions. So the alloy may matter. (yes his employer unwittingly supplies the analysis facility!)

Posted

I've seen various methods for assaying the amount of aluminum in an alloy. However, I am unsure how suitable they are for a MgAl alloy. Some are as simple as digestion with NaOH, thorough washing and massing. That specifically came from an alloy of Nickel and aluminum. Though not very common, it was used to test for remaining Al in Raney Nickel catalysts. I saw another, though I don't remember the alloy, where it was dissolved in HCl and allowed to sit for several weeks to months to allow the AlCl3 to hydrolyse, where it could then be massed.

 

The best test would probably be melting point, but this involves developing a standard curve first if one cannot be found.

 

Dissolving in nitric acid, neutralizing, and titrating the Mg content with EDTA may also prove acceptable. Probably quite accurate as well when done by a trained chemist.

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