NeighborJ Posted November 11, 2016 Posted November 11, 2016 Strobes are one area of pyro which I have neglected except for the Yankee flashers. I've avoided them due to the commonality of AP in most strobing stars. I have nothing against AP except for the extra steps needed for priming and the ignition problems involved. I'll get to it all eventually but for now I'm exploring the non AP stars and the first one I'm trying is this red... 60 SrNO3, 20mgal,10sulfur,10dex. I'm patiently waiting for them to dry. I'm looking for other nonAP strobes which are good proven comps. Blue, green, yellow... Thanks
dynomike1 Posted November 11, 2016 Posted November 11, 2016 I hope you find them. The best i have got with nitrate strobes is a flitter. Maybe because i rolled and pumped them.
NeighborJ Posted November 11, 2016 Author Posted November 11, 2016 I have the best hopes for the red because a chlorine donor is not necessary. I believe it could be difficult to make parlon flash without very coarse MgAl. But why would there be so many different formulas if none of them work? I just need my field of view narrowed to find a few which have worked well for others.
PIL Posted November 12, 2016 Posted November 12, 2016 Actually nitrate green strobe is easier to reach a satisfying color depth than the red nitrate strobe ,which appears to be pinkish . HCB Green strobe is superior, achieving both good frequency and color depth. However red strobe formula is hard to tune .It usually ends up with a flickering red or a violently-flashing pink.Anyway I'm looking forward to seeing your results.
Arthur Posted November 12, 2016 Posted November 12, 2016 Strobes are notoriously fussy of precise ingredient details. Sometimes it's a narrow mesh cut of metal fuel sizes,
NeighborJ Posted November 12, 2016 Author Posted November 12, 2016 (edited) I think I know where to get the MgAl. I tested A Star last night (not dry yet) but it was more of a salmon color and it did flash violently. It will still be a while before they are completely dry and then primed. The formula I have for green is exactly the same with the Sr subbed with Ba. I think I should give it a few days to dry completely and retest before I try the green. I'd like to do a test and try a little CuNO3 with the same formula, the problem there is keeping it dry. Edited November 12, 2016 by NeighborJ
PIL Posted November 12, 2016 Posted November 12, 2016 I think I know where to get the MgAl. I tested A Star last night (not dry yet) but it was more of a salmon color and it did flash violently. It will still be a while before they are completely dry and then primed. The formula I have for green is exactly the same with the Sr subbed with Ba. I think I should give it a few days to dry completely and retest before I try the green. I'd like to do a test and try a little CuNO3 with the same formula, the problem there is keeping it dry.Copper nitrate[Cu(NO3)2] attacks magnalium .
NeighborJ Posted November 12, 2016 Author Posted November 12, 2016 PIL, thanks for the info, I always want to be made aware of safety issues and possible reactions. Could K dichromate provide enough protection? I assume it would be an acid so would it not have a reaction with just Al? I don't expect it to work as a strobe without a lot of testing. Just curious. Thanks.
PIL Posted November 12, 2016 Posted November 12, 2016 Cu（II） is a mild oxidizer, but strong enough to oxidize reactive metals (Mg，Al ...).The reaction is known as single-displacement reaction .And yes ,cupric nitrate solution is acidic due to hydrolysis . I doubt that the passivation layer would be strong enough. It seems that you're going to try making blue strobe. To make blue strobe, something exotic is needed such as guanidine nitrate to cool down the flame . Good blue strobe effect is very hard to produce because a hot flash can easily destroy the CuCl species.
NeighborJ Posted November 12, 2016 Author Posted November 12, 2016 I do recall some months ago someone had made a post referencing the use of guanidine nitrate in strobes but no formula was given at the time because it was a little off topic for that discussion. I do have it and I've tried using it to cool down some regular blue stars but had abandoned the idea when the resulting stars would pulse inconsistently. Not the effect I was after at the time but I'd certainly be willing to revisit the possibility of its use as a strobe if I could find a compositional starting point.
OldMarine Posted November 12, 2016 Posted November 12, 2016 (edited) Kaj Fredriksson just posted results of some tests he was doing assessing different nitrate strobe comps on FW and the guanidine nitrate formula rated above the average of his tests for strobe distinction and ignitability. Edited November 12, 2016 by OldMarine
NeighborJ Posted November 12, 2016 Author Posted November 12, 2016 Ugh, I suppose yer gonna force me to switch over to the dark side and join a PAY site. That's ok they finally have info I want which I can't find here.
OldMarine Posted November 12, 2016 Posted November 12, 2016 You'll be tickled. I'm on all three big ones and all have their place. APC is by far the best place to posit "What if?" and "Why can't I?" type questions. Although many of the same guys and gals are here as are on FW, their tone seems to soften a bit here. The formulary and articles are the main reason to go "To the Dark Side" but I'd avoid the political shit (I'm trying but....)
NeighborJ Posted November 14, 2016 Author Posted November 14, 2016 OK, the red strobes are finally completely dry, so I figured I'd show a video of the ground test. It is most definitely a salmon color but it's all nitrate and it strobes. They'll need primed before I put them in a shell they are also the hardest stars I've ever made at 10% dex they sound like marbles clacking together. red strobe test.mp4
dynomike1 Posted November 14, 2016 Posted November 14, 2016 I wonder why i cant get mine to strobe like that. I don't have any problem with white just red and green.
PIL Posted November 14, 2016 Posted November 14, 2016 Strobe rate decreases if you light a corner of an unprimed star in comparison with a fully primed one.
NeighborJ Posted November 14, 2016 Author Posted November 14, 2016 I have another experiment to do with this strobe. I'm going to dip the star 1/2 in NC then dust it with various chlorine donors. It will be a kind of pillbox strobe and with the chlorinated skin, it should make a more true red.
ExplosiveCoek Posted November 15, 2016 Posted November 15, 2016 I would decrease the dex and add parlon in this one. Giving them a chlorinated skin will probably make them fire retardant.
dynomike1 Posted November 18, 2016 Posted November 18, 2016 (edited) Yea OM i feel the same way. You would think some of them are running for congress. Edited November 18, 2016 by dynomike1
Yus Posted October 19, 2018 Posted October 19, 2018 Jennings-White Blue Strobe First Tests. Compositions are under video. https://youtu.be/odu16aJSXgc 1. NH4ClO4 - 50%, (NH4)2SO4 - 25%, AlMg - 20%, Cu - 5%.2. NH4ClO4 - 50%, (NH4)2SO4 - 25%, AlMg - 15%, CuAl2 - 10%.
Adrenaline Posted October 20, 2018 Posted October 20, 2018 Thanks a lot Yus, I've always wondered what these strobes actually look like. Could you give a few more details? What binder did you use? AlMg and Cu particle size? Did you make the CuAl2 ?
Voryon Posted October 20, 2018 Posted October 20, 2018 Hi Yus, I´ve tried the formula No. 1, but it resulted in a very fierce burning violet star without strobe. Additionally when I tried to bind with NC lacquer the mixture started to heat up and released strong ammonia smell. Quantity has been small as I always keep it small with new and unknown mixtures. As I realized the generation of heat I let the mix alone outside and it cooled down again as well as dried up. I wanted to post this to remind everyone that AP and metals do not go too well together! I´ve always been interested in strobes in general and also finding a stable formula for blue or violet strobes without too exotic/expensive chemicals, to date without success. Partial success was there but relies on Copper powder and AP which does not store for long, you can see the copper turning to green after a week.
Yus Posted October 21, 2018 Posted October 21, 2018 (edited) Adrenaline, 10% NC was as a binder. AlMg, Cu and CuAl2 are commercial powders with partical size less than 0.1 mm or 3 micron (Cu).Voryon, I dried powders after milling. I agree that it is not easy to store such compositions. Commercial blue strobe probably contain nitrogen-based organic compounds. 1:13 Blue strobes https://youtu.be/SoorruvKP5E Edited October 21, 2018 by Yus
PhoenixRising Posted October 22, 2018 Posted October 22, 2018 That's such a rich effect. I think they still looked a touch Turquoise compared to the blue stars up front. Tom R. had a turquoise strobe that was good, not sure that's up for sharing though. It's on video somewhere on one of his many amazing rocket displays.
Mumbles Posted October 31, 2018 Posted October 31, 2018 If formulas bound with NC lacquer started giving off ammonia rapidly, the solution is probably wet. This was a big problem with parlon bound poured go-getters a number of years ago. Acetone can absorb a pretty substantial amount of water, and NC itself is kind of hard to dry. Combined, I'm not surprised it could start up a reaction. I've wondered if using other solvents with less water miscibility might help. Toluene or Xylene are sort of what I was thinking about. It helps to slow down evaporation too to prevent condensation as well.
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