laser200 Posted August 24, 2009 Posted August 24, 2009 Ok..Seems like i saw on here something about flash powder being speak easy...But I want to learn to make this correctly and safety for burst boost.....Not so much as salutes....Im very weary of this and it gives me the creeps just hearing about doing this. But I need it I think...I have heard of slow flash for a burst .I want the most stabilized formula there is..Can someone lead me to the right direction please? Yep im fairly new..I have only sent 3 3" shells up and 1 4"...With pretty darn good success might I add..... I just need a harder break for some shots I have planned for...
Weasel Posted August 24, 2009 Posted August 24, 2009 (edited) The safest flash formula without any doubt is standard 70/30 KCLO4/Al . Fast flash powder is made with super fine 2 micron aluminum. "Slow flash" is made with -325 mesh bright flake aluminum. If you have made a 4 inch shell, you are most likely not a begginner. If you are scared to touch flash, you could think about using whistle mix as a booster instead, it is a bit safer. wait a minute... your first shell was a 3"? and you have sent up 3? and one 4"? okay, first of all you should really start with much smaller shells. And I wouldn't reccomend messing with flash if you have only made 4 shells. Edited August 24, 2009 by Weasel
50AE Posted August 25, 2009 Posted August 25, 2009 I think that a more safer formula than the 70:30 is the nitrate one 50:30:20 and it works good for shell boosters.
scarbelly Posted August 25, 2009 Posted August 25, 2009 I thought 70:30 was safer due to nitrate flash having the issue of nitrate and aluminum reacting... am I correct?
flying fish Posted August 26, 2009 Posted August 26, 2009 wait a minute... your first shell was a 3"? and you have sent up 3? and one 4"? okay, first of all you should really start with much smaller shells. And I wouldn't reccomend messing with flash if you have only made 4 shells. With some guidance...it's not at all bad to start with 3" + shells. They are easier to make and often less frustrating for beginners. The key is that they understand the danger of the larger shells, and are building and firing them in a safe manner. That's why I say..."with guidance." Any beginner's shell-building class at a club shoot is not going to start them off with miniscule shells - The one that I saw they were building 5"ers. As for nitrate flashes...I'd worry more about Nitrate flashes made with more reactive metals...like uncoated magnalium or magnesium, compared to nitrate flashes with plain old aluminum. Yes, the nitrate and aluminum CAN react in the presense of water/moisture to liberate heat + NH3, but it only becomes a problem with sufficient moisture and with sufficient insulation to prevent the heat from escaping. The "safety advantage" of nitrate flashes is simply that they are not anywhere's near as sensitive, or as powerful. Even 70/30 made with bright flake Al is much more powerful and sensitive than nitrate flash made with dark Al. Perc flashes can be set off with the smallest static discharges, as well as impact such as a medium hammer blow. Nitrate flashes require a larger static spark, and are much harder to set off by impact. Typically when working with flash you should have prevention measures against electrostatic discharge. My method is rather crude and perhaps impractical...I just "lay off" the flash until the humidity is above a certain threshold, which I've loosely defined as "when I walk outside and water condenses on me." I'm exaggerating slightly, but this humidity extreme obviously presents other problems for fireworks making. The better way to do it is to have an ESD safe mat like they use for handling sensitive electronics, or some other well-established product for ESD prevention. And then of course you have your "common-sense" practices which are important not to overlook reguardless of whether you are working with flash or some other composition - generally eliminating sources of heat, spark, flame, friction, etc. This includes removing "sparking" metals such as steel and Titanium from the work area, removing flammable solvents, unplugging anything with a motor, etc, etc. I suppose writing posts like mine carries a certain danger to it. I might accidentally give the impression that we can tell you, in this thread, everything that you need to know to "safely" work with flash. I suggest you go through the other flash-related saftey threads in this section...I believe some contained links to saftey guidelines written by "authorities" on the topic.
Ralph Posted August 26, 2009 Posted August 26, 2009 Weasel um eachart 5413H super is 3 micron and Indian pyro 100 is 2-4 micron so im not sure what your talking about so there is really no 2 micron out there and it is generally accepted that nitrate flash made with some kind of dark al is slow and that made with other more energetic oxidisers is fast. as far as sensitivity nitrate flash isnt that hard to set off with a hammer I think they are fairly much even with sensativity but KClO4 is clearly faster and therefore more dangerous and like the others said might be worth getting a little more experience before you start messing around with flash beacuse once you do you need to keep an area isolated from everything elce were you can make the flash with out getting it on all of your other pyro stuff
TrueBluePyro Posted August 26, 2009 Posted August 26, 2009 I dont think anyone can say there is a 'safe' flash powder, they are all dangerous and very sensativity, just that some are alot more the others. Just stick with BP for the moment, flash isnt nessceary as of yet. I started with 3" shells and got some pretty nice breaks with just BP on wheat hulls.
50AE Posted August 26, 2009 Posted August 26, 2009 Of course, there is no non sensitive flash powder and care should be taken with any of them. I'm happy of using the nitrate flash with paint Al grade and it won't self ignite unless it is highly confined and very moist. If some guys worry about it, you could add some boric acid to make it more resistant.
laser200 Posted August 27, 2009 Author Posted August 27, 2009 Ok..Thank you. Yes it will be some time before I make any. Im in the Star making and strobe phase right now anyway. The only reason i would want any of this stuff is for something like a hard break on my Bright red stars. Since they light easy and burn for a while it would look good to break them hard and spread them out more. I have been using bp coated rice hulls and Im just getting very soft breaks on my 3 inch shells. Im putting 4 layers of paste wraps on them. Scott
50AE Posted August 27, 2009 Posted August 27, 2009 4 layers is not enough, even if you're using 70lbs craft paper. I put like 14-16 layers of 35lbs craft
Arthur Posted August 27, 2009 Posted August 27, 2009 IMO a 3" shell is a good place to start! They are small enough to fill with a reasonably small amount of material, yet they are large enough to break with good BP! As you are using a paper shell case a 3" will break well with good BP and plenty of layers of pasting. Smaller shells need a faster break charge, under pasted and nothing will give you a good break. Go look at pyroguide.com for some charts on layers of pasting on ball and cylindrical shells. The break system for plastic hemis will be different! Don't mix or confuse the two til you are certain that you have one of them done really well
Swede Posted August 29, 2009 Posted August 29, 2009 I am into the habit of testing every comp I've ever made for impact and friction sensitivities. Some guys might not know this, but just about every single perchlorate comp I've tried has had impact sensitivity. A simple organic-fueled color star snaps and pops easily under the hammer. It's just the nature of the beast. If you are testing on concrete, try a block of steel as a backing instead for the hammer test. Steel on steel will definitely pop much easier than steel on concrete. I think what sets FP apart is static more than impact. Whatever the mechanism, it demands respect, but too much respect becomes fear, and that makes you unsafe.
r1dermon Posted October 14, 2009 Posted October 14, 2009 The safest flash formula without any doubt is standard 70/30 KCLO4/Al . Fast flash powder is made with super fine 2 micron aluminum. "Slow flash" is made with -325 mesh bright flake aluminum. If you have made a 4 inch shell, you are most likely not a begginner. If you are scared to touch flash, you could think about using whistle mix as a booster instead, it is a bit safer. wait a minute... your first shell was a 3"? and you have sent up 3? and one 4"? okay, first of all you should really start with much smaller shells. And I wouldn't reccomend messing with flash if you have only made 4 shells. whistle mix is not any safer than flash...it's quite sensitive and needs to be handled in the same manner as flash. regardless, for a booster, i've used several nitrate oxidisers with varying success for applications in slow flash.
dagabu Posted October 14, 2009 Posted October 14, 2009 whistle mix is not any safer than flash...it's quite sensitive and needs to be handled in the same manner as flash. regardless, for a booster, i've used several nitrate oxidisers with varying success for applications in slow flash. I will take you to task on that. Swede, you have impact sensitivity test results on both 70/30 and benzo whistle? I Have to find the right one but AFN had several articles on sensitivity of perchlorate mixes and placed whistle on the bottom. Oil, wax or paraffin retarded the reaction significantly. Dave
r1dermon Posted October 14, 2009 Posted October 14, 2009 dagabu, im not contesting whistle to be as sensitive, but the potential energy release and the brisance are in the general areas of flash powder, especially when using salicylate, which, lets face it, most people making whistles are probably making them with salicylate these days. even if it takes more of a shock to set it off, it still contains enough energy to do real damage. im just saying that the same precautions should be taken with whistle as flash, to downplay the dangers associated with it is asking for trouble.
firetech Posted October 14, 2009 Posted October 14, 2009 The break system for plastic hemis will be different!Hey whats the difference? I've used both and come up with similar results in the sky, but on the ground the paper shells are ripped to shreds or torn for the most part. Where as my plastic shells never break or shatter-they just split apart.
dagabu Posted October 14, 2009 Posted October 14, 2009 dagabu, im not contesting whistle to be as sensitive, but the potential energy release and the brisance are in the general areas of flash powder, especially when using salicylate, which, lets face it, most people making whistles are probably making them with salicylate these days. even if it takes more of a shock to set it off, it still contains enough energy to do real damage. im just saying that the same precautions should be taken with whistle as flash, to downplay the dangers associated with it is asking for trouble. Gotcha!! While we are at it, add strobe to the mix since it is just as common as whistle and flash and takes much less impact to ignite then whistle of any mix. D
dagabu Posted October 14, 2009 Posted October 14, 2009 Hey whats the difference? I've used both and come up with similar results in the sky, but on the ground the paper shells are ripped to shreds or torn for the most part. Where as my plastic shells never break or shatter-they just split apart. Hmmm, my plastic 3" hemis don't split and dump. Have you been using whistle mixed with your hulls or used a pinch of flash to break the shell harder? I use 200# strapping tape and do two passes vertically on the entire shell, it makes for a closer fit in the gun and ensures that it doesn't come apart at the equator. D
firetech Posted October 14, 2009 Posted October 14, 2009 Well I'm speaking in terms of 1.75'' shells, which could very easily make a difference. And yeah, I break them with a bit of whistle. Don't have flash (yet). I have using paper hemi's more recently, because I like them more. When I use plastic though I usually hold them together with 35lb strapping tape. Either that or a sh!tload of pasting. Don't get me wrong, they break HARD, but just not the hemi's themselves. It really doesn't make a difference as long as the break looks good. I just assume they would break under that kind of stress.
r1dermon Posted October 14, 2009 Posted October 14, 2009 Gotcha!! While we are at it, add strobe to the mix since it is just as common as whistle and flash and takes much less impact to ignite then whistle of any mix. D might as well...but then again, i would contest that most strobe compositions spend a lot more time "Wet" than whistle mix or flash in powder form intended to break/boost a shell...
Swede Posted October 15, 2009 Posted October 15, 2009 I will take you to task on that. Swede, you have impact sensitivity test results on both 70/30 and benzo whistle? I Have to find the right one but AFN had several articles on sensitivity of perchlorate mixes and placed whistle on the bottom. Oil, wax or paraffin retarded the reaction significantly. Dave I attempted to make a standardized drop rig, but it was a failure. I think a better route is a hammer that drops through an arc, from 9:00 to the target at 6:00. Without a standardized setup, it's hard to gauge how impact sensitive a comp is. You can guess and come close, but it would be really nice to have repeatable results. The hard part is creating the target. It's a bit more complex than just piling a bit of comp on a hard surface and smacking it. I'm thinking the easiest would be a stainless steel female form, a male piston, and a loading chamber for the comp, with obvious vent holes to expel the gasses. That cartridge assembly gets mounted in a firm fixture for the impact. I love experimenting, and this is definitely something I need to construct.
Mumbles Posted October 15, 2009 Posted October 15, 2009 Swede, I'll see what I can do for you, but I do believe there are diagrams and explanations of all the test rigs in Principles of Pyrotechnics by Shidlovskii. Impact, friction, heat, etc. They have others that I am more interested in like the flame spectrophotometer. I could possibly scan them in for you sometime if you're interested.
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