Fire-Man Posted June 26, 2008 Share Posted June 26, 2008 I was planning on adding some silver tails to some of my shells that I made. The comp is these are in percentages Potassium Perchlorate 50 Aluminum, flake, bright. -325 mesh, 36 micron 35 Barium Nitrate 10 Shellac 5 How do you know if you should or not screen, mortar pistil, and ball mill stuff? Sorry for the newb question, just want to be safe. This seems like a flash sort of compound, so I am guessing that I wouldn't ball mill this?? What about this? Potassium Chlorate 40 Potassium Nitrate 25 Sulfur 20 Copper(II) Carbonate 15 Link to comment Share on other sites More sharing options...
FrKoNaLeaSh1010 Posted June 26, 2008 Share Posted June 26, 2008 The first one should be fine for milling although i would mill everything but the aluminum and then screen in the aluminum afterwards. As far as the second composition I would never make that and definitely not mill it because of the chlorate and sulfur. Link to comment Share on other sites More sharing options...
frogy Posted June 26, 2008 Share Posted June 26, 2008 Never mill metals at all, unless you really know what you are doing, and definitely never mill a metal in a composition, or any mill jar\media that have contacted an oxidizer. Never, ever mill Chlorate and Sulfur... Contacting is enough, but my god, slamming balls onto it ( sounds awkward). Link to comment Share on other sites More sharing options...
bmarley5780 Posted June 26, 2008 Share Posted June 26, 2008 METALS = NO Just keep that I mind and you'll be ok. Altough there are other reactions that can take place if you have copper media...Someone else willl chime in on that. Link to comment Share on other sites More sharing options...
Bonny Posted June 26, 2008 Share Posted June 26, 2008 For the first comp you have listed (and many other comps) I would only mill the oxidizers together. Add the fuel/metal/colour donor after and mix by screening.The second comp I would forget you ever saw it... erase it from your memory and hardrive. A good start would be BP and related compositions. As for having asked about milling a chlorate and sulfur comp, you should stop everything NOW and do A LOT of reading before going any further, and stay away from the chlorates until you know more about them.I'm not trying to rag on you, but nobody wants to see anyone get hurt. Link to comment Share on other sites More sharing options...
flying fish Posted June 26, 2008 Share Posted June 26, 2008 Sulfur and Chlorate are a BIG incompatibly...it will most likely explode if you mill it, and you definetely shouldn't even mix it in the first place. Personally, I do not use chlorates because I prefer to not have to worry about cross contamination with BP based formulas and other things that contain sulfur, and in general I don't want things blowing up in my Garage. People that work with chlorates should have a damn good idea what they are doing. As has been said, milling metals powders is always a bad idea as well. Especially when you are talking about a mixture that contains Perchlorate and a very reactive aluminum like what you mentioned. You only need to mill things if they are not already fine enough to use as they are, or if you are making basic black powder (Potassium Nitrate, Sulfur and Charcoal). When working with chemicals that may be incompatible with your other chemicals, you NEED to have separate milling containers and milling media, utensils, etc... Link to comment Share on other sites More sharing options...
Fire-Man Posted June 26, 2008 Author Share Posted June 26, 2008 I have built tons of BP stars. Like tiger tail. I also built electric white. The second comp was supposed to be blue. Does anyone know of a simple comp I can use to make blue, red, or just about any other color. Since chlorate in unstable? I have the basic chemicals. Is this still dangerous? Potassium Chlorate 16 Barium Nitrate 12 Shellac 4 Dextrin 1 Link to comment Share on other sites More sharing options...
50AE Posted June 27, 2008 Share Posted June 27, 2008 Hmm, about ball milling of metals. 1. Can't we use 2 drums with different medias ? One for oxidizers, and one for metals. 2. To avoid pyrophorics reactions from oppening the drum after a long time milling, can a hole be punctured in the drum, while it's turning, to let oxygen come in and oxidize the metal powder little by little, during all the milling process? It will be located in the center of the lid of the drum, and a filter will be put on, to prevent metal powder from falling. The problem is, that the hole will be cloged up from the dust and no air will enter in. Still, if you want to mill powders, you need to be careful. A member burned severly his hand, because he dropped one of the steel balls in his drum full with milled magnesium. The ball created a spark and ignited the powder, that burned him. Link to comment Share on other sites More sharing options...
Mumbles Posted June 27, 2008 Share Posted June 27, 2008 1. I still wouldn't recommend it. 2. Nope. That person would have been Bob Forward, and I believe the jar was actually empty, just residues. A full on Mg fire would have done much more damage. Don't even consider the use of chlorates. I don't care how experienced you think you are (because you're not). The simple fact that you even have to ask should be enough to know you're not ready. Most color stars are not ball milled at all. Most compositions don't need to be ball milled. If your chemicals are coarse, grind them individually and screen together. Link to comment Share on other sites More sharing options...
FrankRizzo Posted June 27, 2008 Share Posted June 27, 2008 Bob's accident was caused by milling magnesium with an unintentional oxidizer. Bob had mixed cab-o-sill, which is a common anti-caking agent and epoxy filler made from SiO2 (sand, glass), with the magnesium to keep it flowing during the milling process. What he didn't realize is that magnesium has a *very* strong appetite for oxygen, even if it's already bound to another atom (note the "O2" in SiO2). Lloyd Sponenburgh (the ball milling book guy) was also involved in a similar accident with magnesium and cab-o-sil. If you mill magnesium, you need bring the particle size down *slowly*, introducing the powder to air multiple times during milling process, and ensure you don't have an unintentional oxidizer present. If you use steel bearings as milling media, they need to be free of rust, as that is an oxidizer when magnesium is involved. May things that you might consider "already burned" or "inert" can be a potential source of oxygen for fine magnesium. It's really best to just buy metal powders pre-milled to whatever size you need. Let the fellas over at Alcoa, Reynolds, Transmet, etc. deal with the safety risk. I include the previous information only because there may come a time in the future where it's impossible to purchase these metal powders and we may be forced to make our own. Know that Both Lloyd and Bob had accidents as a direct result of milling with an oxidizer. Link to comment Share on other sites More sharing options...
flying fish Posted June 27, 2008 Share Posted June 27, 2008 Hard to believe that a small quantity of silica could spontaneously oxidize even the most reactive metal powders, but I guess it is possible seeing how other oxides certainly can. Cab-o-sil is of course extremely fine silica (basically nano particles). But still, considering how little cab-o-sil is actually added as a dispersant, that would be like mixing 2 grams of Potassium nitrate with about 100 grams of Charcoal and expecting it to burn, wouldn't it? I'm interested in more info on how that conclusion was reached if anyone happens to know. Another idea...for metal powders, would it be a bad idea to continuously introduce air intentionally to keep up the oxide coating? It probably is, so that's why I'm going to say don't try it. But everyone says that you have to open up the jar from time to time to allow the protective oxide coating to form. If that were the case, what would happen if you continuously allowed the magnesium access to fresh air, by installing an air filter on your mill and forcing air into it? Again, probably a terrible idea, but I'm just throwing it out there. Link to comment Share on other sites More sharing options...
FrankRizzo Posted June 27, 2008 Share Posted June 27, 2008 Hard to believe that a small quantity of silica could spontaneously oxidize even the most reactive metal powders, but I guess it is possible seeing how other oxides certainly can. Cab-o-sil is of course extremely fine silica (basically nano particles). But still, considering how little cab-o-sil is actually added as a dispersant, that would be like mixing 2 grams of Potassium nitrate with about 100 grams of Charcoal and expecting it to burn, wouldn't it? I'm interested in more info on how that conclusion was reached if anyone happens to know.Lloyd's (the 'unnamed pyrotechnician') accident from '98 (also published in AFN): http://groups.google.com/group/rec.pyrotec...08ec24628a28908 Bob Forward's accident: http://groups.google.com/group/rec.pyrotec...gnesium&lnk=ol& Link to comment Share on other sites More sharing options...
flying fish Posted June 27, 2008 Share Posted June 27, 2008 I guess it is more believable when it was 70grams of SiO2 and 300 of Mg. I had pictured just adding in a pinch to help disperse the powder, but it appears he had the SiO2 as nearly a quarter of the mix by weight... Still, it didn't sound like anyone in those threads had actually proposed that the SiO2 oxidizing the Mg was the "direct" source of the ignition or explosion. Of course, I didn't really understand all the stuff the chemist said...since I'm not a Chemist... Link to comment Share on other sites More sharing options...
FrankRizzo Posted June 27, 2008 Share Posted June 27, 2008 Nor did I say it was the "direct" source of ignition. Obviously, it was a mechanical/static issue in Lloyd's accident and definitely a mechanical issue in Bob's situation. What I said is that they were both putting energy into a system that contained both an oxygen-hungry fuel and an oxidizer...a definite no-no. Link to comment Share on other sites More sharing options...
50AE Posted June 27, 2008 Share Posted June 27, 2008 Damn, the accident is nasty . I would mill some metals, like Fe, Al, Ti, that are not so reactive like Mg is. Link to comment Share on other sites More sharing options...
frogy Posted June 27, 2008 Share Posted June 27, 2008 Have you researched milling metals much? Probably not very much.... Milling aluminum is also very dangerous if you do not know what you are doing. You must went the mill periodically, and monitor the temperature of the Aluminum so it doesn't become pyrophoric. If your aluminum is too hot, and doesn't gradually build an oxidation layer, whenever you do get to opening the mill, it will basically ignite like flash powder from all the oxidation happening at once. Link to comment Share on other sites More sharing options...
Swede Posted June 27, 2008 Share Posted June 27, 2008 It would seem that a jar full of Mg dust, with even minute impurities like a pinch of Cab-o-sil, could ignite in one location, at a minute level, due to the interactions of the contaminants with the Mg... the ignition would then spread due to the presence of free O2. There have been cases of machinists turning magnesium having horrible accidents. One in particular that I read about, a gent was well on his way to turning a Mg bar down to size, and had generated a thick pile of Mg chips on his lathe bed. Warned "you better clean that lathe off NOW", he decided to press on. The oily Mg chip pile ignited, and cut the lathe bed in two. So once finely divided Mg begins to burn, in the presence of O2, it will continue to burn. Link to comment Share on other sites More sharing options...
Bonny Posted June 27, 2008 Share Posted June 27, 2008 The oily Mg chip pile ignited, and cut the lathe bed in two. So once finely divided Mg begins to burn, in the presence of O2, it will continue to burn. I remember reading/hearing somewhere that Mg can even burn in sand as the heat is intense enough I guess to free the oxygen up and keep the flame alive. Link to comment Share on other sites More sharing options...
frogy Posted June 27, 2008 Share Posted June 27, 2008 Mg is quite scary... Before I was into pyrotechnics much, someone gave me a coffee can full of pretty clean magnesium turning (no oil and very little mixed turning... some copper\plastic\steel). I was burning it by the cup, just in piles... What I'd do now for a few pounds of Mg for alloying Link to comment Share on other sites More sharing options...
50AE Posted June 27, 2008 Share Posted June 27, 2008 Have you researched milling metals much? Probably not very much.... Milling aluminum is also very dangerous if you do not know what you are doing. You must went the mill periodically, and monitor the temperature of the Aluminum so it doesn't become pyrophoric. If your aluminum is too hot, and doesn't gradually build an oxidation layer, whenever you do get to opening the mill, it will basically ignite like flash powder from all the oxidation happening at once. No I haven't never. Sorry then, I spoke only from the experience of other pyros who already milled metals with average precautions. But I'll gladly read a book about ball milling, if I find one Link to comment Share on other sites More sharing options...
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