Ubehage Posted October 20, 2014 Posted October 20, 2014 This may be a stupid question, that is already covered in another thread. If so, please delete this and help me find the right one I have been making some "Jumping Jacks", simply by plugging a tube, drilling a home in the side (at the end of the tube), and filling it with BP, 60/30/10.The reason I used this composition, is because I had some left, and decided to try it out for different purposes. And for Jumping-Jacks, it worked perfectly.I need to mention, that this composition was not granulated. It was only screened. However, I have made 3-4 batches of this, and all works the same way. This time, I decided to cook it together, and granulate.But when I make the same kind of JJ's, they just explode. With a thumb *POP*. That puzzles me... How come, granulated BP will burn so much faster?
dagabu Posted October 20, 2014 Posted October 20, 2014 Surface Picture this, fill a glass up with water, how much surface is there? Just the exposed water on top. Fill the glass with small ice cubes, how much surface area do all those ice cubes have together? Granulating (within limits) BP has the same effect, the flame propagates through the BP faster when there is more surface to burn. *Powders may not have more surface than the face of the mass and may burn slower. *Generally not the case with energetic compounds like flash. 1
BurritoBandito Posted October 20, 2014 Posted October 20, 2014 This time, I decided to cook it together...What do you mean by "cook it together"?
Ubehage Posted October 20, 2014 Author Posted October 20, 2014 What do you mean by "cook it together"?I mean, dissolve the KNO3 in boiling water, then add the sulfur and charcoal to the watery mixture, OFF the heat
BurritoBandito Posted October 20, 2014 Posted October 20, 2014 Are you crashing the slurry out in acetone or something to avoid having the KNO3 form big crystals? I'm not trying to rag on you or anything. I'm just curious about your procedure.
Ubehage Posted October 20, 2014 Author Posted October 20, 2014 No. I only use plain water, and dextrin as binder.I granulate as soon as the mixture reaches a workable state; not too liquid. And let it dry until it no longer feels moist to the touch.Then I granulate again, through a finer sieve, until it becomes powder-like. And I let it dry again, untill it does not feel colder than the air surrounding (Colder, from evaporation of water).
enanthate Posted October 20, 2014 Posted October 20, 2014 I assume you don't have a mill? Or else, why all this trouble? 1
BurritoBandito Posted October 21, 2014 Posted October 21, 2014 Given the fact that your process does not involve milling the powder, I would assume that a large part of the performance increase you're observing comes from having a much more intimate mixture by dissolving the KNO3 in water, as opposed to just screening the components together. Still, IMO, there is no substitute for actually milling your BP. 1
dagabu Posted October 21, 2014 Posted October 21, 2014 Ub is making pulverone in the Mike Swisher style. The boiling water allows the kno3 to fully incorporate into the charcoal. Crashing in a cooling bath makes it hotter. That's not what cylinder shell guys are looking for but Ub is. 1
enanthate Posted October 21, 2014 Posted October 21, 2014 Sorry a bit offtopic, but do you guys normally use the 75:15:10 formula when making BP or the optimal one (74.6:13.5:11.9)?On the numbers it looks to me like there should be a rather significant difference. Will try it out, meanwhile what do you guys do?
Ubehage Posted October 21, 2014 Author Posted October 21, 2014 Sorry a bit offtopic, but do you guys normally use the 75:15:10 formula when making BP or the optimal one (74.6:13.5:11.9)?On the numbers it looks to me like there should be a rather significant difference. Will try it out, meanwhile what do you guys do?I usually make 75:15:10, mostly because it is very easy to work with those numbers. And because so far, it has served my needs.I will try out your formula next time, thank you.
Seymour Posted October 21, 2014 Posted October 21, 2014 I've seen quite a few 'optimal' ratios for black powder. They are often made with a single use in mind, often guns or just for lifting shells. In at least some of the cases, the difference in ratios is a result of making up for variations in quality of materials from what is normal, or to account for losses in processing. In firework use there seems to be very little benefit from using them. Maybe some, but definitely not enough to convince a lot of people. Who cares in it takes one less gram of BP to lift a shell? You can make much larger increases in quality via better charcoal and processing than by using slightly different ratios. I know I seem negative. There is absolutely nothing wrong with using other ratios to improve quality, I'm just giving my perspective on why 75/15/10 reigns supreme in popularity. 1
taiwanluthiers Posted October 21, 2014 Posted October 21, 2014 Using the right charcoal makes a heck of a difference. Try it with Paulownia vs BBQ lump charcoal, the difference is huge. Dissolving the kno3 in hot water, then crashing it in alcohol seems like the CIA method. I have never tried it but heard it works... except that alcohol tends to be somewhat expensive... If you are concerned about safety mill the bp in 2 separate steps. First step is kno3 with 1/3 the charcoal (no sulfur), then the rest of the charcoal along with the sulfur. The milled mix is screened together, and when granulated with hot water, makes for a rather hot bp. The charcoal used will even affect rocket performance by a large degree too, I used to make end burning rockets out of willow charcoal that would work fine (it barely took off with BBQ charcoal), but when paulownia charcoal was used, it would CATO every time.
dagabu Posted October 21, 2014 Posted October 21, 2014 In this case, the crashing is done in separate vessels using ice water, not alcohol In this case, the crashing is done in separate vessels using ice water, not alcohol
VaterAraignee Posted October 22, 2014 Posted October 22, 2014 Using the right charcoal makes a heck of a difference. Try it with Paulownia vs BBQ lump charcoal, the difference is huge. Dissolving the kno3 in hot water, then crashing it in alcohol seems like the CIA method. I have never tried it but heard it works... except that alcohol tends to be somewhat expensive... If you are concerned about safety mill the bp in 2 separate steps. First step is kno3 with 1/3 the charcoal (no sulfur), then the rest of the charcoal along with the sulfur. The milled mix is screened together, and when granulated with hot water, makes for a rather hot bp. . You don't crash in alcohol, well I suppose you could but "that would" be expensive. You crash in ice water to prevent the kno3 from forming larger crystals, then you rinse out the water with alcohol to further prevent larger crystals and speed up processing time.Isopropyl alcohol isn't expensive. I can get 4 quarts of %50 for $1.06.Add about $0.25 in salt per quart.shake vigorouslyallow to settledecantnow you have a little over 2 quarts of %85+ on the cheap.
Sparx88 Posted October 22, 2014 Posted October 22, 2014 (edited) neat trick, with the salt, thanks, will try it out 90% is'nt all to expensive but I like simple experiments like this. Knowledge right? Edited October 22, 2014 by Sparx88
VaterAraignee Posted October 22, 2014 Posted October 22, 2014 neat trick, with the salt, thanks, will try it out 90% is'nt all to expensive but I like simple experiments like this. Knowledge right? don't try it with booze, well maybe tequila. You wont get all the water out of suspension, but you will desolve salt into all of the water.adding enough salt that it wont completely desolve then warming the solution to and shaking more will allow even more water to drop out.If I remember correctly you can't get higher than 90.some odd percent and wold need a reflux still to hit about 95 and vacuum to break that. Any still including the revers pot lid still will clean out the salt but you'd also lose a lot of alcohol with cheap stills making it only good for playing at experimentation.I should probably legaly change my name to JOAT.
modelrocket Posted October 23, 2014 Posted October 23, 2014 I'm actually pretty surprised noone has ever made a video comparing all the different methods/formulas/charcoals/grain sizes. 1
Ubehage Posted October 23, 2014 Author Posted October 23, 2014 I'm actually pretty surprised noone has ever made a video comparing all the different methods/formulas/charcoals/grain sizes.I agree.My guess is, that the various methods produce so much different results, that people who are "pro" would never degrade themself. And people like me, don't know the neat tricks.So a video can't be made
modelrocket Posted October 23, 2014 Posted October 23, 2014 I agree.My guess is, that the various methods produce so much different results, that people who are "pro" would never degrade themself. And people like me, don't know the neat tricks.So a video can't be made xD, I wish my country would allow me to make bp, id make the video . But no, bp is "dangerous".. so I have to stick to r-candy
dagabu Posted October 23, 2014 Posted October 23, 2014 There is no "pro" at r-candy, it's all seat if the pants experimentation.
modelrocket Posted October 23, 2014 Posted October 23, 2014 There is no "pro" at r-candy, it's all seat if the pants experimentation.I'm sorry I don't know that expression... what does it mean?
MrB Posted October 23, 2014 Posted October 23, 2014 Invent it as you go. Flying by the seat of your pants is something along the lines of improvisation/instinct.B!
modelrocket Posted October 23, 2014 Posted October 23, 2014 Invent it as you go. Flying by the seat of your pants is something along the lines of improvisation/instinct.B!Ahh, I'm doing the exact opposite for a school project, I have come up with a theoratically perfect composition, I'll be testing and comparing it soon
Ubehage Posted October 23, 2014 Author Posted October 23, 2014 Ahh, I'm doing the exact opposite for a school project, I have come up with a theoratically perfect composition, I'll be testing and comparing it soonFrom my time with R-candy, I came up with 100 KNO3, 50 Sugar, and 20 Glucose. Dissolve in 150ml water, and let it dry. 1
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