THEONE Posted December 2, 2012 Share Posted December 2, 2012 http://www.youtube.com/watch?v=juZUp5jfoA0 Has anybody try this one ?? Link to comment Share on other sites More sharing options...
AirCowPeacock Posted December 2, 2012 Share Posted December 2, 2012 It works. It won't be German Dark, but it will be fine dark Al. Link to comment Share on other sites More sharing options...
THEONE Posted December 2, 2012 Author Share Posted December 2, 2012 It looks really very reactive... I really want to make a homemade ball mill but i can not find anywhere any good source of steel balls... Link to comment Share on other sites More sharing options...
AirCowPeacock Posted December 2, 2012 Share Posted December 2, 2012 Find your local surplus store. Mine has 100s of pounds of steel balls for cheap. Link to comment Share on other sites More sharing options...
MrB Posted December 2, 2012 Share Posted December 2, 2012 The fella in the clip say's to open the jar every 4 to 6 hours, as a means of avoiding ignition when finaly opening it. To me this seams counter initiutive. Am i way of, or would you be better of leaving it, and if your worried about ignittion, turn the mill of, but don't open the can?B! Link to comment Share on other sites More sharing options...
Algenco Posted December 2, 2012 Share Posted December 2, 2012 The fella in the clip say's to open the jar every 4 to 6 hours, as a means of avoiding ignition when finaly opening it. To me this seams counter initiutive. Am i way of, or would you be better of leaving it, and if your worried about ignittion, turn the mill of, but don't open the can?B! it will heat up as it oxidizes, if allowed to do it all at once it will very likely catch fire.Similar to milling MgAl, the cap should be removed for a few seconds then closed, wait a couple of hours and repeat.This allows the oxidation to occur slowly Link to comment Share on other sites More sharing options...
spitfire Posted December 2, 2012 Share Posted December 2, 2012 What about adding some material to coat it. (or at least slow down a reaction) by adding Graphite or charcoal, maybe even materials with a ''greasy'' nature Like spirit or anything with a low viscosity or some material that won't disturb the final use of the material. Link to comment Share on other sites More sharing options...
THEONE Posted December 2, 2012 Author Share Posted December 2, 2012 That is why they add charcoal to the AL, it protects it from oxidation and it make it more reactive. Link to comment Share on other sites More sharing options...
MrB Posted December 2, 2012 Share Posted December 2, 2012 it will heat up as it oxidizes, if allowed to do it all at once it will very likely catch fire.Similar to milling MgAl, the cap should be removed for a few seconds then closed, wait a couple of hours and repeat.This allows the oxidation to occur slowlySo it's the adding of oxygen thats the issue, not the heat from repeated pounding in the mill. Cool, i had no idea. Thanks.B! Link to comment Share on other sites More sharing options...
THEONE Posted December 3, 2012 Author Share Posted December 3, 2012 Find your local surplus store. Mine has 100s of pounds of steel balls for cheap. I dont think so that we have got any store like that here in Greece. Link to comment Share on other sites More sharing options...
flying fish Posted December 3, 2012 Share Posted December 3, 2012 A word of caution, according to an incident report that was part of a safety article I was reading recently (from passfire) those rapid oxidation fires can happen instantly as you open the jar. I'd be prepared for the worst by wearing the appropriate PPE (perhaps a face shield) and pointing the milling jar away from yourself when you open it. The risks are probably low if you open the jar at the appropriate times but the amount of damage a mill fire can do to you is more than you'd think. As far as making german dark Al, the first step is to move to germany... Link to comment Share on other sites More sharing options...
psyco_1322 Posted December 3, 2012 Share Posted December 3, 2012 I like the heavy use of hot glue on that kids equipment, obviously some quality work there. Link to comment Share on other sites More sharing options...
laserkoi Posted December 3, 2012 Share Posted December 3, 2012 It looks really very reactive... I really want to make a homemade ball mill but i can not find anywhere any good source of steel balls... you can get steel balls from any survival store / gun shop ask for catapult ammo / slingshot ammo . you will find it in 6mm to 10mm is common but some stock it up 13mm and its cheep Link to comment Share on other sites More sharing options...
Mumbles Posted December 3, 2012 Share Posted December 3, 2012 That is why they add charcoal to the AL, it protects it from oxidation and it make it more reactive. They don't add charcoal to the Al in the industrial production process. That method at best is a cheap knock off bound to yield an inferior product. Link to comment Share on other sites More sharing options...
MrB Posted December 4, 2012 Share Posted December 4, 2012 I'm just thinking. (still) Using a disposable container to mill your dark AL, just leave it running. (We already decided it wasn't energy buildup, but rapid oxidation as you let air in that was the cause for concern?)Once your convinced it's fine enough, or if you used a see through container, know it's fine enough for your use, turn it of. Poke a SMALL hole in the lid. Leave it. The oxygen able to get inside the jar will slowly oxidize the AL, but shouldn't allow for rapid oxidation, and as such limit the heat, and eliminate the risk for rapid heat increases, and fire. Yes? (I'd advice not to try this based on my theory alone, but as far as i can figure, this should be safe, if all we have to contend with is rapid oxidation, and heat as a result from that.)It's not that much of a bother to simply open the jar regularly, but seeing as people have very different mills, the process is more or less effective for every setup, so if 3-4 hours is safe for some, it may not be a safe time frame for others. What about adding some material to coat it. (or at least slow down a reaction) by adding Graphite or charcoal, maybe even materials with a ''greasy'' nature Like spirit or anything with a low viscosity or some material that won't disturb the final use of the material.They do use linseed oil for MGAL, and / or straight MG. Guess it could work for AL to. But i'm not sure about adding it to the "milling" phase, or how much to add. 1-5% is used for MG/MGAL if i remember right. Oh, and it turns sticky to some degree, hence i'm not sure about adding it pre milling... B! Link to comment Share on other sites More sharing options...
Algenco Posted December 4, 2012 Share Posted December 4, 2012 save yourself some aggravation / disapointment and very possibly serious injury and buy it. Link to comment Share on other sites More sharing options...
Algenco Posted December 4, 2012 Share Posted December 4, 2012 taken from Starmolecule German Blackhead Aluminum Powder & Indian Blackhead Aluminum Powder are just different in one aspect, the country of origin. Blackhead is a special process. Aluminum is made into a very thin sheet. It is then glued to a piece of paper. The paper is shredded down to a fine powder (probably around 200 mesh or so). Then it is put into a kiln and the paper is burned off. This is what gives it it’s dark color. The powder is then hammer milled to make even finer. They end up averaging around 8micron or smaller depending on the time allocated for processing Link to comment Share on other sites More sharing options...
Arthur Posted December 4, 2012 Share Posted December 4, 2012 Part of the issue is that aluminium doesn't mill well to small particle sizes, it agglomerates to bigger particles as well during milling and hits a size plateau where the abrasion and the agglomeration are in equilibrium and the product gets no finer for greater milling.Adding things moves the equilibrium and gives finer product. Link to comment Share on other sites More sharing options...
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