AdmiralDonSnider Posted August 12, 2010 Posted August 12, 2010 (edited) Yep, Bonny. Don´t ever try to grind it in a plastic-case blade mill by the way! They work well with 50:50, but the 70:30 went straight through the wall :-). I´d love to hear some experiences about the physical properties of 70:30 for comparision. I don´t know if it´s intended to be that hard to break up, or if anything went wrong with my ratios... Edited August 12, 2010 by AdmiralDonSnider
50AE Posted August 15, 2010 Posted August 15, 2010 Ready to melt a 1300g batch of MgAl. I spent a lot of time to cut the Al oil pan and the Mg gearbox with one of these big angle grinders. Messy work and this tool is so heavy and powerful. I was totall covered with Mg-Al dust and went to take a shower. http://store.picbg.net/thumb/7E/50/bfc37d6310847e50.jpg
Mumbles Posted August 15, 2010 Posted August 15, 2010 That sounded like the start to a story about how you accidentally spontaneously ignited.
AdmiralDonSnider Posted August 15, 2010 Posted August 15, 2010 That sounded like the start to a story about how you accidentally spontaneously ignited. You could protect yourself with some potassium dichromate...
50AE Posted August 31, 2010 Posted August 31, 2010 (edited) Lesson learned when making MgAl guys!Don't be tempted to melt MgAl in a too long container. I mean, you can, but don't fill it to the top. Denser Al tends to sink to the bottom and lighter Mg goes to the top. Now I have Mixed MgAl, where I can only break the middle part, the top and bottom are inbreakable and I'll melt them again.By the way, here are some photos of making it with a pepper baker. http://store.picbg.net/thumb/18/94/5c382bf108401894.jpg http://store.picbg.net/thumb/5D/8B/6e6ba876c6195d8b.jpg http://store.picbg.net/thumb/1B/13/072e96dfed911b13.jpghttp://store.picbg.net/thumb/E3/66/862ea5bcb502e366.jpg http://store.picbg.net/thumb/2D/EC/70a7639951292dec.jpg http://store.picbg.net/thumb/02/E5/6b48243a6c1902e5.jpghttp://store.picbg.net/thumb/14/2C/1c6012ca6520142c.jpg Edited August 31, 2010 by 50AE
Bonny Posted September 2, 2010 Posted September 2, 2010 Lesson learned when making MgAl guys!Don't be tempted to melt MgAl in a too long container. I mean, you can, but don't fill it to the top. Denser Al tends to sink to the bottom and lighter Mg goes to the top. Now I have Mixed MgAl, where I can only break the middle part, the top and bottom are inbreakable and I'll melt them again.By the way, here are some photos of making it with a pepper baker. The problem you have is that the material is not mixed properly.The container size/shape, is not the problem. I have experienced the same issue witha wide, shallow container that was not sufficientlty stirred. Very simply, the melt was not well mixed. IIRC correctly I posted this exact problem on here quite some time ago...as per FrankRizzo I would recommend re-melting the whole batch. It is most likely the unbreakable ends contain a larger % of Al, so you want to bring it back to the intended ratio.
dagabu Posted September 2, 2010 Posted September 2, 2010 A long handled tea spoon works great in the lead pot for stirring, wouldn't a stainless tea spoon work for this as well?
Bonny Posted September 2, 2010 Posted September 2, 2010 A long handled tea spoon works great in the lead pot for stirring, wouldn't a stainless tea spoon work for this as well? A stainless spoon would work , as will a rod (stainless or even clean mild steel)
50AE Posted September 2, 2010 Posted September 2, 2010 I stirred for about half and a minute after everything had melted. Maybe the rod surface has to be in mind. I stirred with a very fin (0.5mm) rod. Gonna attach a spoon to it for next time.
dagabu Posted September 2, 2010 Posted September 2, 2010 A stainless spoon would work , as will a rod (stainless or even clean mild steel) You need more surface area then a rod to make a good homogeneous mixture.
AdmiralDonSnider Posted September 18, 2010 Posted September 18, 2010 I don´t know how many of you have messed around making other alloys than the common 50:50, but for those who plan to do so: I have made 70:30 I was under the impression that the 70/30MgAl was 70% Mg.... which indeed is 70% magnesium (I was wrong earlier in this thread) and called for in some colored star formulas (in Hardt, Baechle), and 30:70 which is said to be superior for crackling microstars. Both are nightmare to reduce to a fine powder; they´re nowhere near as brittle as 50:50. 30:70, being high on aluminum, is the hardest of the three to grind, but 70:30 is not much better (but is more bulky). I´d appreciate any suggestions how to conveniently reduce these to a useable size. Kitchen macerators work well for the usual alloy, but have a hard and short life with others. I assume that even a ball-mill would have its troubles with 30:70...
Bonny Posted November 5, 2010 Posted November 5, 2010 I´d appreciate any suggestions how to conveniently reduce these to a useable size. Kitchen macerators work well for the usual alloy, but have a hard and short life with others. I assume that even a ball-mill would have its troubles with 30:70... The way I (rough) break my MgAl up is in a coffee can with a pc of steel shaft (and a bag over top to keep the pcs in the can). Maybe something that would work for you - using a heavier can. After that a (large) ball mill with heavy SS or chrome bearing media. You also might want to try pouring the alloy melt into water as a few members do, it (might) make it more brittle.
dagabu Posted November 5, 2010 Posted November 5, 2010 The way I (rough) break my MgAl up is in a coffee can with a pc of steel shaft (and a bag over top to keep the pcs in the can). Maybe something that would work for you - using a heavier can. After that a (large) ball mill with heavy SS or chrome bearing media. You also might want to try pouring the alloy melt into water as a few members do, it (might) make it more brittle. Careful of steam explosions if you do this. I do lead shot the same way for Cowboy shoots, if you let too much molten liquid out at once, it boils the water and throws it out of the cooling tank. I use a 5 gallon metal can with the garden hose running full open to keep the water cold.
AdmiralDonSnider Posted November 5, 2010 Posted November 5, 2010 The way I (rough) break my MgAl up is in a coffee can with a pc of steel shaft (and a bag over top to keep the pcs in the can). Non-standard alloys such as 70:30 or 30:70 really are different: I hit the ingots with a large hammer and they just kept smiling at me. The problem is that these alloys aren´t brittle at all, they tend to be flexible instead, like the parent materials. Nothing to be crushed easily, really.
Bonny Posted November 6, 2010 Posted November 6, 2010 Non-standard alloys such as 70:30 or 30:70 really are different: I hit the ingots with a large hammer and they just kept smiling at me. The problem is that these alloys aren´t brittle at all, they tend to be flexible instead, like the parent materials. Nothing to be crushed easily, really. You might be SOL in reducing the particel size by normal/practical means...Machining/grinding could be your best option.Maybe you could freeze with nitrogen and then smash
FlipperFuego Posted August 15, 2019 Posted August 15, 2019 Very Cool, nicely done! http://freeimagehost.info/i/EmLd7t6Zzb.png
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