Guest gregulimy Posted January 31, 2013 Posted January 31, 2013 hello people of the forums recently i have made a batch of standerd BP and its very bad it just "fizzles" then goes out i tried milling the components separately before mixing and didn't do much i need help thanks-greg
psyco_1322 Posted January 31, 2013 Posted January 31, 2013 Let's start with a simple history. Have you ever made good BP with those exact same chems?
Guest gregulimy Posted January 31, 2013 Posted January 31, 2013 nope i used 75g kno3 15g charcoal 10g sulfur
taiwanluthiers Posted January 31, 2013 Posted January 31, 2013 what kind of charcoal did you use? it makes a really big difference.
Guest gregulimy Posted January 31, 2013 Posted January 31, 2013 um not to sure because im new i didnt know what charcoal to buy so i got some off my countries auction site thing
nater Posted January 31, 2013 Posted January 31, 2013 You said you milled the components seperately and then mixed, and it just "fizzled". Did you mill the BP together at all or just screen it? What, if any, processing did you do after it was "mixed"?
Guest gregulimy Posted January 31, 2013 Posted January 31, 2013 no i didnt mill them together because i herd it is unsafe and no processing after mixed
nater Posted January 31, 2013 Posted January 31, 2013 (edited) Well then, what you have is "green mix" and not BP. What you experienced is pretty much how it burns. Take what you have left, dampen it with water until it feels like modeling clay. Then rub it through a 12 mesh screen or coarse kitchen colander onto a tray lined with newspaper. Spread it out thin and let it dry in the Sun. Then burn a little more. You should see an improvement, but it still won't be great. BP really needs to be ball milled together for the best results, then the milled dust is granulated and dried. Various binders and techniques give different results. Edited January 31, 2013 by nater
CrossOut Posted January 31, 2013 Posted January 31, 2013 You will need to mill your BP for a few hours or grind it in a mortar and pestle. dont worry there is not dangers of doing this as long as you use non sparking media inside a safe grinding container. as Taiwan mentioned the charcoal you use is a huge factor. you will want to go with plum, willow, balsa, polownia, or pine. if you ever buy skylighter's charcoal i will say now that their charcoal is Crap for BP but it is great for stars. finally you will want to make sure all of the chemicals are dry, toss each in the oven separately at ~250 degrees F or ~110 C for a good 45 minutes.
taiwanluthiers Posted January 31, 2013 Posted January 31, 2013 If you're afraid of milling them together, what I do is I mill all of the kno3 with 1/3 of the coarcoal, and the next batch I mill the rest of the charcoal with the sulfur and binder. Then you screen the two together a few times to mix them. This has yielded fast powder with Paulownia charcoal. Doing it this way means that there will be no chance that it will explode since kno3 with very little fuel won't burn at all (I tried, all it did was melt the kno3 and produced no reactions). I can't say what it would do in kilogram quantities though...
psyco_1322 Posted February 1, 2013 Posted February 1, 2013 First off, don't be afraid to mill BP, it's how everyone makes good BP, including the industry. Do some research, figure out what you need to mill bp. I often refer to a mill as being like a Drivers License, you just can't do a whole lot with out one. Secondly, you can't use charcoal briquettes, they are loaded with clay. Search around, find out what charcoals work well (willow, alder, paulownia, pine) and see what you can get locally or for cheap. Even green mix, which is just what we call bp that has been screened together, will burn up pretty well. Nothing should stop burning before it has all been consumed. If your comp stops burning, there is definitely something wrong with it. Next question, did you get the chems from a reputable supplier, or is it something you bought at your local garden store?
skipflashboom Posted February 1, 2013 Posted February 1, 2013 To Gregulimy - I use the same blend of ingredients you list in the standard 75 - 15 - 10 mix. I worried about milling all ingredients together as well. I have found that ball milling them all together is the key! My "rule of thumb" has been that the longer you mill them, the stronger your BP will be. In my experience; 4 hours = weak combustion (Great for wood dust fireballs!), 20 hours = I launched a baseball over 200 feet with .5 oz (14 grams). I guess that Dextrin makes a more durable "grain?" but is not necessary. Dextrin is basically corn starch that has been baked at 400 degrees for many hours.
Seymour Posted February 1, 2013 Posted February 1, 2013 With milling BP safely there should be the expectation that it will explode for planning purposes, even if all materials are considered safe. Contamination and possible causes of other freak accidents can be real, and its reckless to not take simple precautions. For example milling 100-200g of powder in even a small yard/garden will limit the likely damage to quite minor levels. In the past I was quite casual about loitering or working beside live mills, but again, this should be avoidable and is an un-necessary risk Many pyros working in unideal situations do produce perfectly serviceable BP by milling oxidizers and fuels separately and screening together and then processing with the wet process, ideally kneading the mass of BP while it is wet before it is granulated. While this method also requires the use of a mill, and is inferior both in quality and because of more labour, it can be made to work in if one has no safe place to mill. To Gregulimy - I use the same blend of ingredients you list in the standard 75 - 15 - 10 mix. I worried about milling all ingredients together as well. I have found that ball milling them all together is the key! My "rule of thumb" has been that the longer you mill them, the stronger your BP will be. In my experience; 4 hours = weak combustion (Great for wood dust fireballs!), 20 hours = I launched a baseball over 200 feet with .5 oz (14 grams).. With an efficient mill, four hours will make awesome BP, though especially with rock tumblers, 20 hours is normal. At the end of the day, if it makes decent BP, it's working I guess that Dextrin makes a more durable "grain?" but is not necessary. Dextrin is basically corn starch that has been baked at 400 degrees for many hours Greglimy, In NZ Corn Starch is known as Corn Flour and that would be 200 deg C. Can you post the specific trademe auction? I've seen a lot of kinds of charcoal on there. It'll probably be useful for something no matter what, but if it's not all that fast, we need to sort out some better stuff for you.
Guest gregulimy Posted February 1, 2013 Posted February 1, 2013 (edited) ok thanks guys ! i will try milling it together Seymour- i will try to find the auctionand i have made some dextrin but dont know if its any good ... any way to test it ? thanks again EDIT- couldn't find the auction has it as been longer than 45 since i have brought it ... I was searching to see if there were any other auctions (of that listing) but none and i think it was hibachi charcoal (not to sure but yeah ) Edited February 1, 2013 by gregulimy
dan999ification Posted February 1, 2013 Posted February 1, 2013 to test your dextrin add some water to it to make a thick paste, it should feel sticky between your fingers, good dextrin will stretch a little sticking your fingers for a moment and be slightly stringy if you pull your finger and thumb from eachother.Bind some bp or stars formula and try to crush it when dry.The ideal way would be to test how much starch has dextrinised, to me not needed for our applications. Three hours in an efficient mill will probuce good bp, i only milled over 3 hour while testing optimum milling time. Dan.
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