Merlin Posted June 27, 2014 Posted June 27, 2014 (edited) I have willow meal powder for granulation with dextrin or red gum 1 Is the best to use plain water and dissolve the dextrin in the water and allow to cooll before wetting the comp2 Use denatured alcolhol and dissovle red gum in that to wet the comp3 Simply screen in the dextrin and use plain water to wet the comp Edited June 27, 2014 by Merlin
nater Posted June 27, 2014 Posted June 27, 2014 Any of the above. I prefer to make a solution of water with 10% dextrin to dampen and granulate the BP. Otherwise known as the Dextrin Liquor Method touted by Gene Yurek.
pyrokid Posted June 27, 2014 Posted June 27, 2014 Red gum/alcohol is too expensive for my liking. Option three has always worked well for me.
Bobosan Posted June 27, 2014 Posted June 27, 2014 Might consider using distilled water rather than tap and a bit of alcohol, say 25%. Don't think the alcohol is really necessary but it does help to break surface tension of the BP components. Distilled water should be free of impurities that may affect BP performance.
dagabu Posted June 27, 2014 Posted June 27, 2014 Have you seen any difference with different sources of water? I only used tap water for BP so i nothing to compare it to.
Bobosan Posted June 27, 2014 Posted June 27, 2014 I've never tried plain tap water to determine if there is any difference. I do know that the calcium content of the water in this area is very high plus the other impurities as reported by the water company in their yearly quality report. Add to that the small amount of sodium introduced by a water softener and it could be troublesome. Distilled water is cheap and I've always used it with any process requiring water.
nater Posted June 27, 2014 Posted June 27, 2014 I have used tap water (city water) without problems. When I build at events, I usually bring a bottle of RO filtered water since I do not know if water is available or what the quality is. I have not seen any difference in performance.
Merlin Posted June 28, 2014 Author Posted June 28, 2014 Well my first BP salute performed well compared to what I turned out before. A little more work on the BP and then I will construct a dummy test shell. Then on to cut stars. Thanks for everyones help.
Bobosan Posted June 28, 2014 Posted June 28, 2014 Which process did you use Merlin? Congrats and if you are happy with the BP, doing the same process again should give you consistent results. Once you feel you have that consistency, then start tweaking.
marks265 Posted June 28, 2014 Posted June 28, 2014 I think the distilled water scare comes from its use with color stars or comps which makes more sense to the purists. In this case some comps may promote reactions because of elements in hard water. Personally I don't worry about it too much for black powder but do use distilled water for star comps merely to avoid problems. And here we go again with red gum and alcohol. This thought reminds me of the little old ladies throwing dollars in a gambling machine and hoping for a great outcome. Makes no sense to me. Regardless of if the process works better or not, a few more grains of bp made with dextrin and water would be fine for me even if it might be the lesser. I would rather buy dextrin and water vs alcohol and water. Since you ask about screening in the dextrin, I assume it is milled? When I mill my powder the mill jar charge includes the dextrin. Merlin, Where any of the above will work, it is up to you and your wallet on what you wish to do. Making black powder is also a general statement because there are many uses for it. The inclusion of purpose would have helped (in the beginning) if we knew this to be lift, break, or pulverone for a few examples. All of which I do granulate for. Are you testing for maroons or lift? Mark
marks265 Posted June 29, 2014 Posted June 29, 2014 Mark, What percentage of Dex do you use?I use 5 percent Dag. I keep telling myself to go down to 4 which I have tested and am fine with thus far. I guess 5 percent is just a round number that sticks when weighing out the comps, so I end up cussing and asking myself "Why do I keep doing this?" I also use a commercial dextrin (from Phil) and not converted corn starch as in the home kitchen oven variety.
Merlin Posted June 29, 2014 Author Posted June 29, 2014 I used 5% dextrin. I used goex as a reference in salutes (maroons) just to judge by the report and casing when my BP was approaching commercial BP. The red gum worked equally well. I like to use acetone or denatured alcohol to reduce drying time and it seems easier to get the consistency right for granulating. I made a dummy shell and successfully fired it using 0.8 oz of the BP. Didnt go as high as I want only about 100-125 feet. I would feel better at 200 ft.
dagabu Posted June 29, 2014 Posted June 29, 2014 I use 5 percent Dag. I keep telling myself to go down to 4 which I have tested and am fine with thus far. I guess 5 percent is just a round number that sticks when weighing out the comps, so I end up cussing and asking myself "Why do I keep doing this?" I also use a commercial dextrin (from Phil) and not converted corn starch as in the home kitchen oven variety. Thanks!
ChrisDeHont Posted August 1, 2014 Posted August 1, 2014 On the same note, I have been in the pyrotechnics industry in the states for 15 years. I have been making shells for 10 of those using commercial BP. With the rising cost of blasting BP to outragous heights, ive decided to make my own cannon grade. I hear alot of talk about people using alcohol vs water to activate the dex. I have been experimenting with different formulas and here are the results shooting a 150g baseball. Desired height is 300 feet. First batch was 75% KNO3 15% willow airfloat 10% sulfur, +4% dextrin. Milled for 5 hours, then formed into a dense clay ball with hot water and grated with a cheese grater. Second batch was the exact same only 100% denatured alcohol was used. Dried over night the water bp granuales were tough but not rock soild and grey. The alcohol bp was very tough. Could not crush and was much darker. I used 1.3 OZ of each to fire the baseball. I used the formula to figure the height of each. Water based total height 289 feet. The alcohol based was 658 feet. Same exact composition and milling but only difference was the water vs the alcohol. Sorry for the long post but for newbies who are havimg trouble getting hot bp this is an option. 1
Jakenbake Posted August 1, 2014 Posted August 1, 2014 On the same note, I have been in the pyrotechnics industry in the states for 15 years. I have been making shells for 10 of those using commercial BP. With the rising cost of blasting BP to outragous heights, ive decided to make my own cannon grade. I hear alot of talk about people using alcohol vs water to activate the dex. I have been experimenting with different formulas and here are the results shooting a 150g baseball. Desired height is 300 feet. First batch was 75% KNO3 15% willow airfloat 10% sulfur, +4% dextrin. Milled for 5 hours, then formed into a dense clay ball with hot water and grated with a cheese grater. Second batch was the exact same only 100% denatured alcohol was used. Dried over night the water bp granuales were tough but not rock soild and grey. The alcohol bp was very tough. Could not crush and was much darker. I used 1.3 OZ of each to fire the baseball. I used the formula to figure the height of each. Water based total height 289 feet. The alcohol based was 658 feet. Same exact composition and milling but only difference was the water vs the alcohol. Sorry for the long post but for newbies who are havimg trouble getting hot bp this is an option.Are you saying you activated the dextrin with alcohol only in the one comp?
nater Posted August 1, 2014 Posted August 1, 2014 Try comparing BP made without dextrin and granulated with alcohol. Some theories are that rapid drying increases the speed of BP and that alcohol is a solvent for some resins left in the charcoal and allow for hard enough granules for our uses. I have made it both ways, but never compared the two.
Bobosan Posted August 1, 2014 Posted August 1, 2014 Water based total height 289 feet. The alcohol based was 658 feet. That's over 100% improvement in height and without doing a similar test myself, find hard to believe.
ChrisDeHont Posted August 1, 2014 Posted August 1, 2014 (edited) Alcohol only.. which doesnt make sense to me as I am a chemistry major and dextrin is soluable in water only... The secret to very hot BP is how fast you dry it. If you use water to activate the dex then the drying time increases 10 fold. Or more. THis is where the problem lies. If you allow your BP to dry to slowly then the KNO3 will recyrstalize within the grains. This in turn will have a drastic affect on the speed of the BP. Meaning when it recrystalizes, the intiment mixture cause by milling no longer exsist. With the Alcohol, it dries with in 20 minutes in my drying chamber. I result from just the difference in water vs alcohol is even noticed by the color of the composition. That's over 100% improvement in height and without doing a similar test myself, find hard to believe.Trust me, when I performed this test I was not prepared for the results. Yes indeed over a 100% improvement. Which in theory means, I can use half as much BP and get the same results. Turning into a big savings of BP per shell. I fully understand if everyone has a hard time believing this. I did myself, and I saw the results first hand. I urge you to try this mixture. If you are interested I can post exactly what I did. Down to the amount of alcohol used.. I will also be doing this experiment again today, but with a 4" dummy shell with both mixtures. I will post the results. Edited August 1, 2014 by NYpyro
Merlin Posted August 1, 2014 Author Posted August 1, 2014 Alcohol only.. which doesnt make sense to me as I am a chemistry major and dextrin is soluable in water only... The secret to very hot BP is how fast you dry it. If you use water to activate the dex then the drying time increases 10 fold. Or more. THis is where the problem lies. If you allow your BP to dry to slowly then the KNO3 will recyrstalize within the grains. This in turn will have a drastic affect on the speed of the BP. Meaning when it recrystalizes, the intiment mixture cause by milling no longer exsist. With the Alcohol, it dries with in 20 minutes in my drying chamber. I result from just the difference in water vs alcohol is even noticed by the color of the composition. Trust me, when I performed this test I was not prepared for the results. Yes indeed over a 100% improvement. Which in theory means, I can use half as much BP and get the same results. Turning into a big savings of BP per shell. I fully understand if everyone has a hard time believing this. I did myself, and I saw the results first hand. I urge you to try this mixture. If you are interested I can post exactly what I did. Down to the amount of alcohol used.. I will also be doing this experiment again today, but with a 4" dummy shell with both mixtures. I will post the results.I also have a chem degree. You are correct in that dextrin is not water soluble. If you use dextrin you have to use a ethanol/ water solution. I don't use dextrin at all but I do dissolve 2% red gum as a binder in ethanol to make a paste and granulate the bp. I thought alcohol only would result in less grain strength. I have found the alcohol/gum method to be far more powerful than water and produces excellent bp for pyrotechnics and also for muzzle-loading rifles.
ChrisDeHont Posted August 1, 2014 Posted August 1, 2014 I agree with the theory that the alcohol should not increase grain strength. But to confirm my results, I milled a new batch last night with the exact same formula. Only this time I used MORE alcohol to dampen the mixture. To the point of a wet surface when formed into a ball. When the grains were dry, roughly 1/4" to 5/16" big, they were almost black and when force was applied, it took even more force to crush the grain. Even then it was not reduced back to a powder like the water base. Very interesting. Goes against everything I know and taught. I will be looking at the particles under a microscope to see the structure. I will let you know what I see. Im sure it has everything to do with the KNO3.
Shadowcat1969 Posted August 1, 2014 Posted August 1, 2014 The grain strength when granulating with 100% alcohol seems to be affected quite a bit by the type of charcoal used, when dried quickly. Ned Gorski says that his alcohol granulated BP (75/15/10 with no binder at all) using eastern red cedar charcoal results in fairly hard grains. I have not tried ERC charcoal yet, but when I use Paulownia the grains, no matter how "wet" the comp and no matter how quickly I dry it, the resulting powder grains are pretty soft and crush easily between my fingers. I have also used a different charcoal (comparable to a commercial airfloat) and that one, when processed identically to the Paulownia batch, results in MUCH harder grains. Both of these, again, use no binder of any kind. In comparison, I have pressed and corned my Paulownia BP, and the power is actually very comparable between the soft grains of alcohol processing and the corned grains when using equal weights. The only real difference seems to be the durability of the grains.
Bobosan Posted August 1, 2014 Posted August 1, 2014 Interesting info here. I also have only used Paulownia but I add 1-2% dextrin to the mill jar and granulate with 75/25 water/alcohol . Going to have to try the willow soon using NYpyro's method. One thing I did notice when milling the willow is it is more dense than Paulownia or Balsa. Charcoal type could be the factor here as Shadowcat pointed out and haven't made BP with ERC either but have some to try. Should be soon since I'm in a BP mill phase at the moment. Usually I granulate BP on a nice sunny day and seems to completely dry within 3-4 hours. Never have experienced KNO3 recrystallizing.
Jakenbake Posted August 1, 2014 Posted August 1, 2014 It has to be very wet to see it crystalize. I have seen it on my blackmatch.
ChrisDeHont Posted August 2, 2014 Posted August 2, 2014 (edited) Ok guys so I made a video today testing 3 differnt batches. Sorry for the video at certian times as it is upside down and when I took the video it said it was right side up then I actually turned it upside down thinking it was already upside down. Phone screen freezes and I cant tell but you'll get the picture. Below are the results in the height. Testing homemade black powder: http://youtu.be/Fg4Wo_bPQI0 results: first test all 26g charges with 3" dummy. #1- 75% 15% 10% +4% dex, water used as wetting agent. 137' #2 same as above with alcohol not water. 332' #3 same as above with alcohol, only difference is I hand mixed the comp much longer and added a touch more. Real difference with the 4" dummy.. 313' Results of 42g charges with 4" dummy, Batch #2 309' too low for a 4" shell Batch #3 755' a touch high but doable. Like I said the only difference with batch 2 and 3 was the amouny of mixing after wetting and the small increase in alcohol. I also compressed the wet mixture in the container by hand before grating.. The 3" BP salute was perfectly timed with 3 seconds at 300' again sorry for the video. Edited August 2, 2014 by NYpyro
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