dave321 Posted May 5, 2011 Share Posted May 5, 2011 i dont make flash but i am curious if the usual 70:30 is impact sensitive to the strike of a steel hammer on a steel surface ? dave Link to comment Share on other sites More sharing options...
Pechovski Posted May 5, 2011 Share Posted May 5, 2011 (edited) I dont think a strike of a steel hammer is something you do to test impact sensitivity, using a hammer in your hand you will still get factors included like amount of force, friction and sparks/heat. You would need to do a drop test for impact sensitivity, and then particle friction would still be a factor to.But i would say yes, anything pyro-related is sensitive to the strike of a hammer. The question might be if 70/30 could be ignited by the strike of a hammer? Ive heard several people say its possible, but requires more work then other flash comps. But still you wouldn't know if the flash was ignited by spark, friction or impact. Edited May 5, 2011 by Pechovski Link to comment Share on other sites More sharing options...
MadMax Posted May 6, 2011 Share Posted May 6, 2011 Yes actually. It's quite easy between a hammer and a steel surface. Nearly every pyro comp is but fp doesn't require much effort. Use mg / mgal or s or p and its way too easy. They won't "ignite" either - when impacted all pyro comps decompose explosively. Honestly, even an oxidizer by itself will. i dont make flash but i am curious if the usual 70:30 is impact sensitive to the strike of a steel hammer on a steel surface ? dave Link to comment Share on other sites More sharing options...
Arthur Posted May 6, 2011 Share Posted May 6, 2011 Flash has so many variables that a drop hammer test could show a wide range of values. Using a 250 mesh powder will yield a different product from using a faster dark or "black" powder. BUT yes flash is a very sensitive pyro compound. Link to comment Share on other sites More sharing options...
dave321 Posted May 6, 2011 Author Share Posted May 6, 2011 The question might be if 70/30 could be ignited by the strike of a hammer? Ive heard several people say its possible, but requires more work then other flash comps. But still you wouldn't know if the flash was ignited by spark, friction or impact. i guess the question should have been .......if a small amount is hit with a hammer will you get a report?whether caused by interparticulate friction, or impact does not matter if it goes bang. i just thought someone may have tried it, out of curiosity. i agree arthur, different compsositions will have different sensitivities, also for different particle sizes etc.the question reffered to 70:30 which is usually made with eckart aluminium or indian blackhead etc. dave Link to comment Share on other sites More sharing options...
dagabu Posted May 6, 2011 Share Posted May 6, 2011 i guess the question should have been .......if a small amount is hit with a hammer will you get a report?whether caused by interparticulate friction, or impact does not matter if it goes bang. i just thought someone may have tried it, out of curiosity. i agree arthur, different compsositions will have different sensitivities, also for different particle sizes etc.the question reffered to 70:30 which is usually made with eckart aluminium or indian blackhead etc. dave You will get a small report from a hammer impact but remember, flash has a lot of power so hitting a 1 gram pile on a driveway or sidewalk can result in temporary hearing loss and missile wounds to the feet. I have no idea if it is caused by particulate friction or "squishy" friction. I am sure that there are many views on the subject but I dont see and difference between any aluminum used with pot perc if it is under 325 mesh, they all pop at about the same time in the hammer test and all light with the flame of cheap chicom time fuse. -dag Link to comment Share on other sites More sharing options...
dave321 Posted May 6, 2011 Author Share Posted May 6, 2011 oki doki, i think the question has been answered, thank you for your views people dave Link to comment Share on other sites More sharing options...
Arthur Posted May 6, 2011 Share Posted May 6, 2011 Remember that "a small amount for testing" is probably only 10 MILLI grammes or 0.01g Link to comment Share on other sites More sharing options...
MadMax Posted May 6, 2011 Share Posted May 6, 2011 It's the oxidizer. The sudden impact causes it to instantly decompose it's oxygen. The presence of a fuel just means the oxygen will have something to react with adding to the power. The metal fuel does contribute in terms of friction somewhat but a more reactive fuel makes it even easier for an impact to set it off. I know because I impact, friction, electricity, and heat test every comp I make. And I've made dozens of types of FP ranging from the least to most sensitive and tested them all this way. If you don't believe me take a small pile (<5mg) of just potassium perchlorate by it self and smash it between two sledge hammers. From a sensitivity standpoint this is -about- the same as the 70/30 so from what I can conclude it's the oxidizer being forced to decompose explosively. The presence of fuel is just a "convenience" for it. Link to comment Share on other sites More sharing options...
pyrochris732 Posted May 7, 2011 Share Posted May 7, 2011 id hate to see this attempted with as much as a gram. Jesus, thats asking for a really bad outcome. Like someone said, try it with a few milligrams. Link to comment Share on other sites More sharing options...
dave321 Posted May 7, 2011 Author Share Posted May 7, 2011 id hate to see this attempted with as much as a gram. Jesus, thats asking for a really bad outcome. Like someone said, try it with a few milligrams. appreciate your concerns, BUT as i said earlier, i dont manufacture flash, it was purely an academic question for perspective thank you all dave Link to comment Share on other sites More sharing options...
dagabu Posted May 7, 2011 Share Posted May 7, 2011 id hate to see this attempted with as much as a gram. Jesus, thats asking for a really bad outcome. Like someone said, try it with a few milligrams. *DANGER* Dont do this!!! OK, since I did the obligatory safety thing, these guys are taping a pound ofg flash to a sledge hammer in Tultepec. Stupid? Yes. -dag http://www.youtube.com/watch?v=IVCQElI5T-A Link to comment Share on other sites More sharing options...
handymanherb Posted May 7, 2011 Share Posted May 7, 2011 Give him his sign, I wonder who caught the hammer Link to comment Share on other sites More sharing options...
Mumbles Posted May 8, 2011 Share Posted May 8, 2011 That is not a normal flash by the way. Link to comment Share on other sites More sharing options...
dagabu Posted May 9, 2011 Share Posted May 9, 2011 That is not a normal flash by the way. As I understand it, it is a chlorate based flash but still a 70:30 mix. Do you have other information on them? -dag Link to comment Share on other sites More sharing options...
Mumbles Posted May 9, 2011 Share Posted May 9, 2011 I was told they were a chlorate/sulfur mixture, perhaps with some aluminum in there. They're definitely chlorate based, though oddly enough that doesn't add a ton of sensitivity to the mixture compared to the perc version. If one were to use a perchlorate 70:30, it'd probably function the same. Link to comment Share on other sites More sharing options...
MadMax Posted May 9, 2011 Share Posted May 9, 2011 Thats gotta hurt. I know by experience that nearby fp explosions actually hurt even if nothing hits you. But yeah I don't think it's straight 70/30 perc. It might also be chlorate whistle mix type comp. I think if you did that with a pound of regular flash you'd probably be dead. I have no idea where this celebration is but this is nuts! *DANGER* Dont do this!!! OK, since I did the obligatory safety thing, these guys are taping a pound ofg flash to a sledge hammer in Tultepec. Stupid? Yes. -dag http://www.youtube.com/watch?v=IVCQElI5T-A Link to comment Share on other sites More sharing options...
dagabu Posted May 10, 2011 Share Posted May 10, 2011 Thats gotta hurt. I know by experience that nearby fp explosions actually hurt even if nothing hits you. But yeah I don't think it's straight 70/30 perc. It might also be chlorate whistle mix type comp. I think if you did that with a pound of regular flash you'd probably be dead. I have no idea where this celebration is but this is nuts! Tultepec Mexico. I would agree, this has to be less powerful or they would all be dead. -dag Link to comment Share on other sites More sharing options...
pyrojig Posted May 10, 2011 Share Posted May 10, 2011 Tultepec Mexico. I would agree, this has to be less powerful or they would all be dead. -dag From my understanding I believe that this is a "red thermite" using red lead oxide and Al metal powder. The two are combined by the impact of the hammer..... This is a kind of stupid that is on a whole new level, for sure.... Link to comment Share on other sites More sharing options...
Rogue Chemist Posted May 10, 2011 Share Posted May 10, 2011 50:50 KNO3/Mg > 40J (Insensitive munition requirement) Professionally measured. Link to comment Share on other sites More sharing options...
pyrojig Posted May 19, 2011 Share Posted May 19, 2011 50:50 KNO3/Mg > 40J (Insensitive munition requirement) Professionally measured. Is this what is being taped to the end of these morons hammers ? That makes a pretty strong flash powder , and is quite sensitive to moisture and if the mag isnt sealed it can be an accident waiting to happen. ( more so with any ammonium compounds than alkaline nitrates) Link to comment Share on other sites More sharing options...
Pechovski Posted May 19, 2011 Share Posted May 19, 2011 (edited) Well all i see is a bag of white comp and 3 containers yellow/pink. The white comp couldn't be flash... but if the containers where flash, even when ive done flash salutes in the day you could see a bright flash inside the center of the smoke. I notice no flash at all when pausing at impact. Edited May 19, 2011 by Pechovski Link to comment Share on other sites More sharing options...
loris94 Posted May 19, 2011 Share Posted May 19, 2011 san juan de la vega (mexico) carnival famous for his sledgehammer festival Link to comment Share on other sites More sharing options...
Rogue Chemist Posted May 20, 2011 Share Posted May 20, 2011 Is this what is being taped to the end of these morons hammers ? That makes a pretty strong flash powder , and is quite sensitive to moisture and if the mag isnt sealed it can be an accident waiting to happen. ( more so with any ammonium compounds than alkaline nitrates) Unlikely.40J is hard to achieve with a hammer hit. This is in the range of low sensitivity things like HNS, TATB, etc. Link to comment Share on other sites More sharing options...
Mumbles Posted May 20, 2011 Share Posted May 20, 2011 Well all i see is a bag of white comp and 3 containers yellow/pink. The white comp couldn't be flash... but if the containers where flash, even when ive done flash salutes in the day you could see a bright flash inside the center of the smoke. I notice no flash at all when pausing at impact. Well, think of chemicals we use that are yellow, and then things they're incompatible with and you're right there. Link to comment Share on other sites More sharing options...
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