Wiley Posted May 17, 2012 Posted May 17, 2012 (edited) This is a question that's been nagging at me for some time now. For my star comps and whistle mix, pure perchlorate is a must. However, studies have shown that some types of perchlorate are quite impure. This perchlorate from HCS seems to be standard, middle-of-the-road material: http://www.hobbychem...chlorate/Detail. How would this perform in whistle mix used as a burst powder? On the other hand is the high purity, recrystalized stuff: http://www.hobbychem...%29-High/Detail. This is supposed to be very pure material (not even any anti-cake), but the price reflects the quality. Skylighter sells 99% purity perchlorate for only $6.50 a pound. Which of these would be the best for purely colored stars and powerful "burst" whistle? Perhaps some of you have used these products and can chime in here. Edited May 17, 2012 by Wiley
Bcorso85 Posted May 21, 2012 Posted May 21, 2012 I made my first whistle mix the other day. I used domestic with no anti cake from rolling thunder pyro. Came out great. Fast as hell when loose, and screamed in a 2 inch tube with 3/8 diameter hole.
MikeB Posted May 21, 2012 Posted May 21, 2012 99% of those guys are full of crap. They have no clue as to what the purity or the source of their supplies are half the time. When you place an order what do you get?A bag or container of white powder. It is up to you to test it to see if it suits your needs. A lot of the material available now is from the surplus market and the re-sellers are just going by the information they received. Several years back I purchased some magnalium. When I mixed up a test batch of stars they started to heat up and decompose. What a surprise. What was supposed to be MgAl was actually Mg.
pyrojig Posted May 21, 2012 Posted May 21, 2012 99% of those guys are full of crap. They have no clue as to what the purity or the source of their supplies are half the time. When you place an order what do you get?A bag or container of white powder. It is up to you to test it to see if it suits your needs. A lot of the material available now is from the surplus market and the re-sellers are just going by the information they received. Several years back I purchased some magnalium. When I mixed up a test batch of stars they started to heat up and decompose. What a surprise. What was supposed to be MgAl was actually Mg. LOL, I too have had the same experience with purchasing what was claimed as Magnalium , and turned out to be Mag. Mike is right, it IS up to the purchaser to test the quality of his or her material. Sadly many people get ripped off when it comes to purity . I guess this is where it is nice to be friends with , or at least know the supplier. The saying is pretty true, " You get what you pay for" and most of these "great deals" out there can be pretty contaminated materials. Thankfully there are smarter fellows than us who have devised methods of testing our materials for purity. . This is where I stress amateurs , stay away from Ebay .
Mumbles Posted May 21, 2012 Posted May 21, 2012 I've yet to come across a perchlorate source that was not suitable. I've heard people say that some of the anti-cake containing products can mess up binding and adhesion to things like rice hulls. That is not something I've personally experienced. I've also heard people say that their chemicals were so contaminated that they couldn't make X color or effect. Again, nothing I've experienced. I've almost always used just the standard "green drum" chinese perchlorate with nothing but success. My blues and purples are just fine. I had access to some fancy chemical instruments a few years ago and actually did do some testing. I was specifically looking for sodium, but in retrospect I should have also tested for calcium. All of the varieties I tested for had low sodium. Oddly enough, the one that tested the highest in sodium at around 0.3% by concentration was Taiwanese, which is known as one of the better varieties.
dagabu Posted May 21, 2012 Posted May 21, 2012 I have used some four different percs now and they all seem to do the same job across the board. I have cheap-o chi-com perc that has a nice whistle, good color in stars and flows nicely. I also have some Swedish perc that is rock hard and have to be blade milled to use that gives the same results. I have been fortunate to not have the same problems as others have had with different percs and just make a batch of red stars and whistle, try them out and call it good. -dag
taiwanluthiers Posted June 6, 2012 Posted June 6, 2012 What about getting Reagent ACS grade for the more critical comps?
dagabu Posted June 6, 2012 Posted June 6, 2012 Sorry, I am just too cheap to buy expensive chems. -dag
Algenco Posted June 6, 2012 Posted June 6, 2012 from all the disusions I've read on the subject, it doesn't make any difference, that said I use Kerr-McGee perc for blues and whistle fuel if I'm redlining, cheap Chi for everything else
Peret Posted June 7, 2012 Posted June 7, 2012 I've never had any "bad" perc, so either I've been lucky, or the frequent criticism one hears of "cheap Chinese perc" is a mixture of prejudice and snobbery. However, it's particularly easy to test for sodium. Just put a little perc on an iron rod in the flame of a gas blowtorch and look at the spectrum. If the yellow sodium line is present, you can't miss it. Don't have a spectrometer? Make one for a dollar.
FrankRizzo Posted June 8, 2012 Posted June 8, 2012 I've yet to come across a perchlorate source that was not suitable. I've heard people say that some of the anti-cake containing products can mess up binding and adhesion to things like rice hulls. That is not something I've personally experienced. I've also heard people say that their chemicals were so contaminated that they couldn't make X color or effect. Again, nothing I've experienced. I've almost always used just the standard "green drum" chinese perchlorate with nothing but success. My blues and purples are just fine. Nor have I, except the "floor sweepings" perc that was sold by FireFox many years ago, and they were pretty clear about the contamination making it unsuitable for anything other than bottom shots. Those solubility tests by Eric H. left me with the distinct impression that he had no idea what he was doing, and/or had some sort of agenda. I know some of the rocket guys are quick to blame the quality of their perc when lamenting whistle rocket performance, but I've found that particle size (fuel, oxidizer, & catalyst) is really the most important variable. I've never had any "bad" perc, so either I've been lucky, or the frequent criticism one hears of "cheap Chinese perc" is a mixture of prejudice and snobbery. However, it's particularly easy to test for sodium. Just put a little perc on an iron rod in the flame of a gas blowtorch and look at the spectrum. If the yellow sodium line is present, you can't miss it. Don't have a spectrometer? Make one for a dollar. That is super cool, Peret! I think my niece will love that project. Thanks for the link. :-)
Potassiumchlorate Posted June 9, 2012 Posted June 9, 2012 At least in Europe potassium perchlorate might be "coarse", i.e. about 80 mesh. In western Europe it's usually milled much finer by the suppliers, though.
Mumbles Posted June 11, 2012 Posted June 11, 2012 I actually received some of the insoluble stuff that Eric harvested from some Perchlorate. I never did get a chance to play with it and see if there was any more perchlorate left in there, or if he really did extract some 30+% insoluble calcium and sodium loaded garbage.
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