Pyroblast Posted July 29, 2007 Posted July 29, 2007 Hey guys, I just joined this forum in hope of some help making black powder.Here's where I'm at.I have a 3 lb ball mill (The same one as United Nuclear sells) with lead media.I got my charcoal and sulfur from United Nuclear (granulated willow charcoal that I powdered in the ball mill).The KNO3 I got off eBay but I know it's good quality because I've made many a smoke bomb with it with great results.I have a scale accurate to 1/10g and measured out a 100 gram batch with the standard 75/15/10 ratio.It has been in the ball mill for 9 hours now, and I'm not very impressed at all. What I have is a gray powder that looks like flash, and burns (relative to what I've seen in videos and commercial powder) quite slowly.It gives off orange sparks of charcoal too. I seem to have hit a dead end. I did everything right, used all the right stuff, yet my black powder sucks.Can anyone help me?Thanks
Polumna Posted July 29, 2007 Posted July 29, 2007 Hi Maybe you have changed the ratios like 75 KNO3/ 15 SULFUR/ and 10 Charcoal, I did that one time and the blackpowder I made looked exactly like your´s. Or maybe your chemicals are not fine enough? Greets, Polumna
Pyroblast Posted July 29, 2007 Author Posted July 29, 2007 No, I measured the chemicals correctly.I powdered the charcoal in the ball mill for an hour before mixing the ingredients. The sulfur was already a very fine powder, like flour.The KNO3 was about the grain size of sugar, maybe a little finer.Besides the ball mill should reduce everything to a very fine powder relatively quickly.The powder is getting slightly darker as I keep milling it. It's been going for 15 hours now. It's a dark gray, but definitely not black. After 24 hours I'm gonna take the meal, corn it through a spaghetti strainer, let it dry, then ball mill it again for an hour or two.As of now the powder still doesn't burn with that satisfying poof I was looking for. Oh well, I'll see what it does...
hst45 Posted July 29, 2007 Posted July 29, 2007 Milled meal doesn't burn very impressively, it needs to be granulated. Try this; mix some water/ethanol into the mix until it's the consistancy of modeling clay. Press this through you spaghetti strainer, let it dry overnight, and report back. My guess is you'll be impressed. Just some advice, too. You could have found this out with a simple search instead of starting a new thread.
Pyroblast Posted July 29, 2007 Author Posted July 29, 2007 Thanks for the help hst45.I did what you said and am now waiting for it to dry. I know from past experiences that in pyrotechnics, when you're 100% sure it's dry, wait twice as long, lol.
mormanman Posted July 29, 2007 Posted July 29, 2007 Let it mill long or make your own charcoal and put that in a blinder and then mills the bp. I don't use powdered charcoal, I don't think it works real good but I don't get a poof and I think that b/c I use pine charcoal.
FrankRizzo Posted July 30, 2007 Posted July 30, 2007 Hey guys, I just joined this forum in hope of some help making black powder.Here's where I'm at.I have a 3 lb ball mill (The same one as United Nuclear sells) with lead media.I got my charcoal and sulfur from United Nuclear (granulated willow charcoal that I powdered in the ball mill).The KNO3 I got off eBay but I know it's good quality because I've made many a smoke bomb with it with great results.I have a scale accurate to 1/10g and measured out a 100 gram batch with the standard 75/15/10 ratio.It has been in the ball mill for 9 hours now, and I'm not very impressed at all. What I have is a gray powder that looks like flash, and burns (relative to what I've seen in videos and commercial powder) quite slowly.It gives off orange sparks of charcoal too. I seem to have hit a dead end. I did everything right, used all the right stuff, yet my black powder sucks.Can anyone help me?Thanks The UN formulation specifies 10% dextrin, which is erroneous. If you use any dextrin at all, the amount should never exceed 4%. Most folks, myself included, use no dextrin. A slight amount of boiling water (4-5% is good) added to the milled powder before pressing will speed-up the burn rate a bit, and help you to achieve optimal density.
Pyroblast Posted July 31, 2007 Author Posted July 31, 2007 How do I go about pressing it?Do I add the 5% water and then compress it down into a solid block?What do I do after that's dry, or do I even let it dry?Sorry about being a total newb by the way.Are there any other ratios for black powder that work well besides the standard one?
ULTRABUF Posted July 31, 2007 Posted July 31, 2007 The best way and the easiest is to go about pressing imo is to just follow the instructions on Dan Williams' site. If you dont have a hydraulic press you will probably need to make or buy one.http://www.pyrotechs.org/dwilliams/press/press.htmlYou will need something in which to compress the bp. http://www.pyrotechs.org/dwilliams/powderdie/powderdie.htmlYou can adjust the size of the powder die depending on how much bp your planning on pressing, for example I made mine with 2 inch PVC instead of 3 inch. You can wet the bp or press it dry. If you press it while wet, you have to let it dry when your done pressing, then you break up your puck into small chunks and size them according to your needs.
moonshot Posted July 31, 2007 Posted July 31, 2007 Milled meal powder will be gray rather than black. I use a tumbler like the UN unit and mill my chems 8 to9 hours max to get a very fine meal BP. Don't be concerned about the gray color it is normal. The powder will turn darker after you wet and granulate it. You said that when you light the powder it gives off orange sparks. This isn't right. It should burn very quickly and just produce a white cloud of smoke so it sounds like your KNO3 may not be very pure. Try this simple test. Put a small pile of your powder on a piece of brown paper and light it . If it burns off the paper without burning holes through the paper it is pretty fast powder. If it burns through the paper it is on the slower side. Hope this helps.
Pyroblast Posted July 31, 2007 Author Posted July 31, 2007 It gives off just a bit of orange sparks. It's really not bad.I put a small pile on a piece of printer paper and while it didn't burn a hole through the paper immediately after burnout, there were some hot specs left over that did burn through in a few spots.The powder is pretty fast, overall I'm pretty pleased, but it just doesn't have that oomph I was hoping for. Next batch I make I'll press and granulate and hope for better results.
saluterocket Posted July 31, 2007 Posted July 31, 2007 before i made myself an actual ball mill, i used a 3 lb rock tumbler also, i found that a mill time of about 20-24 hours gives the best results.
Pyroblast Posted July 31, 2007 Author Posted July 31, 2007 What exactly is the difference between a dedicated ball mill and a rock tumbler?I mean, the tumbler I have is the exact same unit that UN sells as a ball mill, so wouldn't it be a ball mill?
Tweetybird88 Posted July 31, 2007 Posted July 31, 2007 before i made myself an actual ball mill, i used a 3 lb rock tumbler also, i found that a mill time of about 20-24 hours gives the best results. Wait. I need to mill for 24 hours in a rock tumbler to make bp? I thought it was only 10. I guess I need to put it back on for a long time.
mormanman Posted July 31, 2007 Posted July 31, 2007 UN sells a lot of mill which one do you have. But really thats not important but yes rock tumblers work just fine. They do the exactly the same thing. On ebay they sell the 40 lbs mill as a rock tumbler. Its a different name for what you use it for. But one problem with the 3 lbs mills/rock tumblers, its the belts so when your belt breaks go to biglots or the dollar store and buy a pound of rubber bands. A pound costs about 5 bucks tops so its real cheap and the real belts may last a week longer that the rubber bands but you can buy a pound of rubber bands for about the same price as one belt. So that all I have to say about that.
FrankRizzo Posted August 1, 2007 Posted August 1, 2007 No, rock tumblers and ball mills are *not* the same thing. A rock tumbler is designed to rotate at low rpm so that the rocks spend more time grinding against each other and wearing their surfaces via the grit. A ball mill instead rotates much faster in order to set-up a cascade action which pulverizes and grinds the material between the media; ideally wearing the media very little in the process. Just because UN markets Lortone and Thumlers rock tumblers as ball mills does not make them actual ball mills. However, that doesn't stop people from using them successfully if run for inordinate amounts of time. What a rock tumbler does in 20hrs, a properly designed ball mill will do in 2-4hrs. To see how badly you're getting screwed by UN, do a Google search for Lortone QT6 or QT12 and Thumlers Model B.
Pyroblast Posted August 1, 2007 Author Posted August 1, 2007 Alright, well my "rock tumbler" spins at about 50 rpm.What speed does a "ball mill" spin at?
mormanman Posted August 1, 2007 Posted August 1, 2007 Ok well my mill spins at about 33 rpm (the drum does anyway). So if my tumbler spun at maybe 45 rpm or 60 rpm the bp in it would be done in 6-12 hours not 2-3 days. Wow. I figured that my tumbler ran 33 rpm and 14 inches in circumference so this is how I got it (if you care at all) 33 rpm*14 inches-----462 inches per minute 462 inches per minute*60 minutes------27720 inches per hour 12/27720=4.32 feet per hour 5280/4.32= 8 mph I don't know how I got that this time but before I got 5.25 mph.Is this fast enough?
FrankRizzo Posted August 2, 2007 Posted August 2, 2007 Alright, well my "rock tumbler" spins at about 50 rpm.What speed does a "ball mill" spin at? The optimal speed depends entirely on the inside diameter of the drum and the size of your milling media. Ok well my mill spins at about 33 rpm (the drum does anyway). So if my tumbler spun at maybe 45 rpm or 60 rpm the bp in it would be done in 6-12 hours not 2-3 days. Wow. I figured that my tumbler ran 33 rpm and 14 inches in circumference so this is how I got it (if you care at all)The optimal speed for a 4" ID tumbler drum with .5" media is 92-100RPM. If your motor is up to the task, you may be able to replace the drive pulleys (and belt) to obtain a faster rotation. McMaster.com has a very nice selection of inexpensive v-belt pulleys.
Pyroblast Posted August 2, 2007 Author Posted August 2, 2007 Alright, well my "rock tumbler" spins at about 50 rpm.What speed does a "ball mill" spin at? The optimal speed depends entirely on the inside diameter of the drum and the size of your milling media. Ok well my mill spins at about 33 rpm (the drum does anyway). So if my tumbler spun at maybe 45 rpm or 60 rpm the bp in it would be done in 6-12 hours not 2-3 days. Wow. I figured that my tumbler ran 33 rpm and 14 inches in circumference so this is how I got it (if you care at all)The optimal speed for a 4" ID tumbler drum with .5" media is 92-100RPM. If your motor is up to the task, you may be able to replace the drive pulleys (and belt) to obtain a faster rotation. McMaster.com has a very nice selection of inexpensive v-belt pulleys. Oh, well I see why my ball mill takes so long to make decent black powder. It's only spinning at best at half the rpm's it should be.I now see what you were saying about the rock tumblers. Even the way it's set up now, my motor gets quite warm and bogs down slightly when the drum is placed on the rotating shafts. I don't think it could handle any higher gearing, so to speak.
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