cvh98 Posted November 5, 2009 Posted November 5, 2009 OK, first off, I hope this is the right place for this question, and second, sorry to bring the subject of Flash Powder up again, but I'm having problems. I made a small batch of flash for some rocket headers and decided to test the mix before assembling the rockets. It didn't go off! I tried another sample, loose over some 1/8th visco, still nothing but a few sparks. I tried some old flash I made last year, which I know was good when I made it as I used it in many rockets with great sucsess. STILL NOTHING! I have had my Potassium perchlorate and aluminium for over a year now in air tight containers in a cold, but dry, shed. Both seemed to be OK, not damp, no lumps, same as before. I mixed them together using the diaper method for 10 minutes or so, same as before. But it fails to ignite. I opened two pots of previously unopened chemicals to try them, (although they are over a year old also). Mixed the usual 70/30, small pile on visco............NOTHING again! My aluminium is 250 mesh to dust, which isn't the best I know, but it has worked. Now my question is, do these chemicals go off? or am I seriously missing something? Please help, these rockets are for tomorrow!
KruseMissile Posted November 6, 2009 Posted November 6, 2009 i can never get my 70/30 kclo4/al to go off too. So i use mgal instead in the 50/50 mix. But I think there are 2 factors. 1 the mesh is too large and 2 it isnt dark(like indian or german).
Ralph Posted November 6, 2009 Posted November 6, 2009 250 mesh is far to coarse you can sit there heating it for ages and it will eventually melt into a blob and if your really patient it will eventually ignite than it is really bright and its quite slow your not going to get a report out of it and by the sounds of things thats probably a good thing
Twotails Posted November 6, 2009 Posted November 6, 2009 I use to have the same Promblem, had 325 mesh Al, but mad it work with 400 mesh Mg. A flash i onec used was Mg/Magnisium sulfate, and worked to a degree. I now have 4500 mesh aluminum, and no longer suffer from problems i had before. I would honestly, ether screen out everything bigger than 400 mesh from your Al, or get new Al.
TheEskimo Posted November 6, 2009 Posted November 6, 2009 Twotails...you have issues with -325 Al. Is it flake or spherical? I have -325 bright flake from skylighter, and it performs like a champ.
50AE Posted November 6, 2009 Posted November 6, 2009 Make sure your aluminium is the flake grade. Spherical won't work.
cvh98 Posted November 6, 2009 Author Posted November 6, 2009 (edited) Cheers Guys, But the thing is, I have already made good flash from these very same chemicals within the last year. I know the aluminium mesh size isn't great, but it has worked with good effect in the past. Do these chemicals "go past their sell by date" after a while? Edited November 6, 2009 by cvh98
Ralph Posted November 6, 2009 Posted November 6, 2009 very fine shepcial aluminium can work for flash and is rumoured to be louder than flake. most of these chemicals (when not mixed) do not really get old but when they are exposed to moisture things change
TrueBluePyro Posted November 6, 2009 Posted November 6, 2009 Im just a bit concered that you had flash stored nice last year? I think it is the Al but you say that it is what you used so maybe it is your kclo4??? I dont know maybe its bad kclo4?
Pyrohawk Posted November 6, 2009 Posted November 6, 2009 It could be a few things. But most likely its that your Al is poor quality.... 250 mesh is pretty big. What do you mean by 250 mesh to dust? Like the Al isn't all consistent mesh? That could be your problem right there....you might have gotten lucky in the past and got enough of the finer Al in your flash to work but this time the majority of it is the larger stuff. True Blue....I think he means he stored the chemicals, unmixed, not the flash. Or I hope so anyway. I say check your scales firstly....if its a crappy scales you may just be off on the ration.Make sure its all dry.Try another batch. If that doesn't work, chalk your past successes up to a fluke. That Al just isn't the grade needed for good flash.
Twotails Posted November 7, 2009 Posted November 7, 2009 Twotails...you have issues with -325 Al. Is it flake or spherical? I have -325 bright flake from skylighter, and it performs like a champ. It was Spherical Atomized Aluminum (5 lbs from UG) Not that im useing 3 micron, there hasent beeen a failed flash yet.
firetech Posted November 7, 2009 Posted November 7, 2009 -325 mesh spherical from UG (underground gadgets?) DOES NOT work for 70:30 flash. Great aluminum, but not for flash.
dagabu Posted November 7, 2009 Posted November 7, 2009 (edited) -325 mesh spherical from UG (underground gadgets?) DOES NOT work for 70:30 flash. Great aluminum, but not for flash. I used three Aluminums last night to dispose of three unruly pumpkins using a 70:30 binary mix in a 1-1/2" paper can. They all worked great with the bright one making less noise but better flash. I took pictures but they are all white, I set the iris too wide, oops! I am thinking its either water or bad pot perc. Andji's Al is exactly like UG's Al, I used it all up last summer at PGI but it was fine for headers. I am sorry its not working but I think that getting a small amount of known good chems (borrow some from a pyro buddy) and eliminating a single bad chem would be the way to go. You will notice that all of my chems (the Super goes in to a Nalgene bottle today after opening it) are stored in air tight containers. That was the first lesson I learned and I drive my buddies crazy with putting the lids back on after every scoop http://www.pyrobin.com/files/can.jpg http://www.pyrobin.com/files/bright%20aluminum.jpg http://www.pyrobin.com/files/bright%20up%20close.jpg http://www.pyrobin.com/files/mikes%205413%20super.jpg http://www.pyrobin.com/files/mikes%20up%20close.jpghttp://www.pyrobin.com/files/andji%27s%20up%20close_1.jpghttp://www.pyrobin.com/files/andji%27s%20aluminun_2.jpg Edited November 7, 2009 by dagabu
Skycastlefish Posted November 8, 2009 Posted November 8, 2009 Agreed. -250 mesh is too large for kclo4 flash. I tried with 350 and it wouldn’t light. I would say 400 mesh would be possible with a dark flake. I recommend 8 micron – 3 micron.
cvh98 Posted November 8, 2009 Author Posted November 8, 2009 Thanks for all the input. I agree that the mesh size of the aluminium is on the limit, so I have ordered some German Dark at 2 microns to try. At least this will determine whether the Potassium Perchlorate is good or not. It's just a bit strange that my old aluminium worked fine when I first got it!! Is it possible to put my 250 mesh stuff in my ballmill with lead balls and reduce it further? Thanks again. P.S. I ended up using Whistle Mix for my rocket headers with very good results.
Ralph Posted November 8, 2009 Posted November 8, 2009 ball milling reactive metals is dangerous and if they are the same lead balls you use for making BP forget about it.
Mumbles Posted November 8, 2009 Posted November 8, 2009 Lead is too soft for this application. Generally stainless steel is more appropriate. You won't be able to make a product that approaches any of the traditionally available flash aluminums by this method. I think you'll be surprised at how long that pound of Al will last you.
firetech Posted November 8, 2009 Posted November 8, 2009 Dagabu are you telling me your -325 mesh spherical Al from UG worked for 70:30?
FrankRizzo Posted November 9, 2009 Posted November 9, 2009 Dagabu are you telling me your -325 mesh spherical Al from UG worked for 70:30? Firetech, It certainly will, but it does need a bit of assistance to generate a nice report with a normal amount of confinement. Attach a flashbag filled with a few grams of 7:3 made with a hot, dark aluminum to the end of the fuse. That will provide the kick-in-the-pants to get the cooler mix going all at once. It's a bit of extra work, but definitely worth it from a cost savings standpoint.
Twotails Posted November 9, 2009 Posted November 9, 2009 If it indeed does work, i think that may be a way i can use up my 4.75lbs of -325 SA Aluminum. Further testing is needed. Also, Seems like i did somthing of intrest least night. I made to batches of 70/30(10g a peice), exept to them i added 1g of finly powderd Hemp charcoal, and to the other 1g lampblack. I set up my testing platform out side, and tested both compositions. One(the hemp) seemed to have a reddish tint to it(doubt it, but it seemed better in comparisan to standerd), the the other(lampblack) seemed to have an abnormaly large flash radius. I mixed the two above together, and seems to have working flash, that, well beats my standard. it looks useful in rocket headers, so i'll have to give it a go.
Mumbles Posted November 9, 2009 Posted November 9, 2009 If there is anything to it, it's likely because the carbon is being used as a fuel first, and the resulting Al must be oxidized by ambient oxygen. It's not uncommon to add additional Al for the same effect. How about you get off the flash kick and use that -325 atomized to make glitters like any normal person.
Twotails Posted November 9, 2009 Posted November 9, 2009 I lack the chemicals for most glitters as of yet, with Xmas coming, i need to make due with what i got(Although I will definity get all or most of the needed chemicals for glitters, crackling microstars, and many other thing when i get my tax rebate in the coming year) I normaly stick to gerbs anyway, being under a mile from a police station dosent help maters.
firetech Posted November 9, 2009 Posted November 9, 2009 Frank, you're right about what you said-I can't deny that. I'm just saying that at least for me the 70:30 mix won't go on its own using the Al I specified.
homebrewed77 Posted November 9, 2009 Posted November 9, 2009 (edited) I lack the chemicals for most glitters as of yet, with Xmas coming, i need to make due with what i got(Although I will definity get all or most of the needed chemicals for glitters, crackling microstars, and many other thing when i get my tax rebate in the coming year) I normaly stick to gerbs anyway, being under a mile from a police station dosent help maters. How about some D1? If you have the chem's to make gerb's with..You can make a hand full of different star's..Hell just a plain charcoal star with added AL look's pretty dang good.. Myself? If I lived that close to the LEO..I wouldnt be making any kind of flash..But that's just me though. EDIT-LOL Mumbles beat me to it. Edited November 9, 2009 by homebrewed77
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