Almamater Posted December 24, 2012 Share Posted December 24, 2012 ive been working with BP for aerial shells for about two years, i made a lot of bp, and thankfully i never had a "big" accident yet, but i keep reading about peoples ball mills blowing up all year round, and im wondering is this bound to happen ? i go 100% safety all day all year round, ive even installed an insane sprinkler system to flood my workshop(its a big ass container), i even got a fallout wall so i can escape.. still the thought of my mill blowing up is quite scary.. thoughts ? Link to comment Share on other sites More sharing options...
AlexPyro66 Posted December 24, 2012 Share Posted December 24, 2012 Nothing is 100% safe.As for ball milling bp is quite safe Link to comment Share on other sites More sharing options...
marks265 Posted December 24, 2012 Share Posted December 24, 2012 The odds are very low when milling bp but freak accidents can happen. This is why you should make sure your mill is up to the task and have a clean work area in a well placed area with plenty of distance. A little story I have: I usually add lump charcoal to my mill and let the mill do the reduction (vs a blender to reduce the charcoal). I usually mill 2 kilo's at a time. One day I was emptying the jars where I pour the contents of the jar through a screen to separate my lead ball media. While returning the sorted media back to the jar I found two iron screws. The screws had to have been in the wood that I cooked for charcoal. I got lucky because the two screws never set off the jar during the duration of the milling time. But did I also get lucky because those two screws never made it to a blender to reduce the charcoal? It is a rhetorical question to get us thinking about any process. Mark 1 Link to comment Share on other sites More sharing options...
Arthur Posted December 24, 2012 Share Posted December 24, 2012 Separation distance is you friend. Put the mill as far away as possible with a remote switch. Link to comment Share on other sites More sharing options...
50AE Posted December 24, 2012 Share Posted December 24, 2012 Emptying the jar can also be a source of accidents, especially when milling metal powders or pyrteochnics mixtures. Some flammable dusts floating in the air can be sensitive to sparks from static electricity. Metal powders can become pyrophoric or easily ignited. There has been a known accident, about a fellow who dropped steel media in almost empty jar from magnesium milling. His hand burned badly with 2nd and 3rd degree burns Link to comment Share on other sites More sharing options...
Potassiumchlorate Posted December 25, 2012 Share Posted December 25, 2012 That's one of the reasons that I never mill metals. Link to comment Share on other sites More sharing options...
TritonPyro Posted March 27, 2013 Share Posted March 27, 2013 How many accidental ignitions have happened with a properly constructed ball mill ( low voltage ) milling ONLY sulphur/charcoal and kno3 and nothing else? I am not talking about what people have heard or ' I read ' or someone told me. Actual stories from pyro's on APC. MILLING WITH PROPER MEDIA AND A SUITABLE JAR. Link to comment Share on other sites More sharing options...
Mumbles Posted March 27, 2013 Share Posted March 27, 2013 I am familiar with at least four separate instances in which the incident was shared first hand with me. One or possibly two of the people are members here. One is potentially from powder leaking into the motor, but it's not entirely clear. Three of the four used ceramic media, and I'm not sure about the fourth. Link to comment Share on other sites More sharing options...
Ferret Posted May 9, 2013 Share Posted May 9, 2013 (edited) I heard something about ceramic media not being safe. When you say ceramic, do you mean the alumina media? Because I have used alumina media advertised for ball mill use for years now, but if it is potentially dangerous I would switch to lead. As far as ball mill safety goes, the motor should be completely separated from the milling area, so that no powder can get to the motor. I also barricade my ball mill with a thick inner layer of Styrofoam surrounded by an outer layer of concrete blocks. The least you can do is prepare for a potential accident. Edited May 9, 2013 by Ferret Link to comment Share on other sites More sharing options...
Mumbles Posted May 10, 2013 Share Posted May 10, 2013 As far as milling goes, I'd have no problems using good alumina ceramic from a known source. There might be a size factor with these alumina media ball mill explosions. Two of the three explosions with ceramic media were relatively large mills, probably 15+ kilos at least. The third was the one with the potential leak into the motor. I don't know much about the composition of the ceramic media of these accidents. I'd be comfortable using high alumina ceramic media from coorstek or something. Link to comment Share on other sites More sharing options...
nesc39 Posted May 19, 2013 Share Posted May 19, 2013 I have used lead media in a plastic tub with BP meal and mixed small batches 2oz far from anyone and never had a mishap but that doesnt mean its safe. Link to comment Share on other sites More sharing options...
SekndAmendment Posted May 22, 2013 Share Posted May 22, 2013 I've seen an instance of an old-timer and his improperly maintained mill with a high-torque motor and gears instead of pulleys that exploded. The bearings on one of the shafts were old, worn, and hadn't seen any grease in years. I even think the mill had been rained on a time or two as well. My guess is the bearings got a bit rusty and operated under tons of friction. The high-torque motor forced them to turn and it generated quite a bit of heat causing something in the mill to catch fire. I don't know what the can was made of but somehow it burned through. One thing led to another and a 1 kilo batch of BP ignited. The mill was outside far from anything and there was no collateral damage.The moral here is that frequent maintenance is good safety practice. Also, some people think pulleys are nice because they allow for slip if something is wrong and friction becomes an issue. Gears continue turning because there is no slip and it either ruins the motor, ruins bearings, or like this old-timer, blows up and ruins everything. Either gears or pulleys work great if you take care of them though. Link to comment Share on other sites More sharing options...
goldwingnut54 Posted May 23, 2013 Share Posted May 23, 2013 (edited) I trust my Lead (Hardened Linotype) media, but I still mill remote, outside, and in small batches of less than 5 ounces of mixed BP. Straight chems get a different treatment and I don't mill metals. 4 ounces of 75-15-10 is GOBS-a-plenty for my muzzleloading needs. But no, it isn't completely "safe" and neither is drinking water, or lying down for a nap (at my age) when you consider how many people choke or die in bed. I mill my BP chems separately, then screen them for foreign matter before combining in my rubber jars. I really enjoy doing it...and if I made a huge batch, I'd just have less time working in a hobby I enjoy. It would be counter-intuitive to make big batches and the safety factor changes with big batches. DUH. If I were into pyro more along the lines of artistic displays, things might change for me. I'm sure my milling practices would. A small batch makes for a small (yet unlikely) accident. Edited May 23, 2013 by goldwingnut54 Link to comment Share on other sites More sharing options...
NeuroticNurse Posted September 18, 2013 Share Posted September 18, 2013 Never milled metals. I've only ever milled black powder, and for that I use lead sinkers in my ball mill, not because I think they're any more safe, but simply because they are physically heavier and denser than the ceramic media, and are more useful for being quicker in smashing up the ingredients into very fine powder.Never heard of any mishaps using the alumina grinding medias though. Link to comment Share on other sites More sharing options...
50AE Posted September 25, 2013 Share Posted September 25, 2013 I've only milled magnalium, but I've always been a bit scared when doing it. True it's not like a live mix, but imagine 2kgs of powder igniting uncontrollably in the drum. Imagine the drum melt, a quick magnalium fire spreading and there's nothing you can do about it. Worse, imagine it igniting when you open the jar and an air-dust explosion follows. I remember I had a strong discipline about it and because it milled so quickly, I always opened the jar every hour. I also remember I had a nightmare while sleeping, the drum caching fire all over . Never wanted to try with magnesium, I felt it was too dangerous. I did mill aluminium though, but it was very slow and PITA. 1 Link to comment Share on other sites More sharing options...
shouldnoteatindat Posted December 30, 2013 Share Posted December 30, 2013 What id do is is get a the steel rim from a tire and then put some boards over it with a concrete block. that way of it blew it would not do a hole lot of anything Link to comment Share on other sites More sharing options...
CannonBall Posted December 31, 2013 Share Posted December 31, 2013 OMG.....After reading all the accidents and precautions that need to be taken i'm surprised i'm still alive. 2 Link to comment Share on other sites More sharing options...
Ragnar Posted January 1, 2014 Share Posted January 1, 2014 Mills metals necessary in inert gas nitrogen, argon, CO2 or propane, butane. Link to comment Share on other sites More sharing options...
Mumbles Posted January 1, 2014 Share Posted January 1, 2014 Carbon Dioxide isn't inert to some of the reactive metals we use. 1 Link to comment Share on other sites More sharing options...
BurritoBandito Posted June 2, 2014 Share Posted June 2, 2014 Sorta reviving the dead here but... A few of you may remember a while back (July 7th 2013) my "what's on your mind" status on APC was about a car accident that my sister was in. When I heard the news I left immediately. One thing that I did not consider was that I had some aluminum in my ball mill. I left my city and went to the hospital where my family was located. I had no idea that I would be out of town for 10 days (my little niece was on life support to preserve her organs so that they would be viable for donations [RIP Monika, I love and miss you]). When I returned to my house I could hear my mill running... Shivers crept down my spine. I (stupidly) decided that the best course of action would be to SLOWLY open my mill. Fortunately, there was no flare up or ignition of any sort. The moral of my story is that, if you are going to mill metals, be vigilant and always make sure to open your jar every few hours or so. I was lucky... You may not be. Backfilling the jar with an inert gas is just asking for trouble. If the metal can not oxidize while being milled, what do you expect will happen when you decide to check on the progress? The instant you open that jar and oxygen is introduced you're likely to have sone serious issues. Also, please read the thread entitled "CONFIRMED - Dagabu is the injured man" for Dags account of his accident while emptying his ball mill. Just because you remotely start/stop the mill does not mean you are in the safe. ALWAYS expect the worse. PPE is a must. 1 Link to comment Share on other sites More sharing options...
dagabu Posted June 2, 2014 Share Posted June 2, 2014 Thanks BB, I agree 100%, FULL PPE is a must. Everyone, the ball mill did not ignite, it was in a safe location and the shed (open on two sides) was just fine. The problem happened when I was unloading the mill, no idea what happened but it did and I got hurt... BAD! Bottom line for me is this: Fire-working is not safe, it is inherently dangerous, to know and understand those dangers, to accept them and do what you can to eliminate them and then don the right clothing etc is paramount. Link to comment Share on other sites More sharing options...
Ddizzle22 Posted June 24, 2014 Share Posted June 24, 2014 This is what i have been wondering myself since I'm new to the hobby very nervous with the whole ball mill and black powder and handling it. I plan on milling as far away as possible and not ever getting close to the mill while its running. Still makes me nervous since its a new chemical that could really mess you up. Link to comment Share on other sites More sharing options...
dagabu Posted June 25, 2014 Share Posted June 25, 2014 (edited) I was milling 22# of BP, the smaller jars, if they flame up on it can be survived with proper PPE, never skimp. Edited June 25, 2014 by dagabu 1 Link to comment Share on other sites More sharing options...
Ddizzle22 Posted June 25, 2014 Share Posted June 25, 2014 I have the 6lb mill that is very commonly seen on the forums. Hoping to start with 150g batches seems like the optimum. Very nervous still of what could happen seems like you had your run in. Link to comment Share on other sites More sharing options...
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