dynomike1 Posted November 7, 2016 Posted November 7, 2016 I started this thread because it might get lengthy. I went with this formula first. Potassium Perchlorate 40, Potassium Nitrate 10, Parlon 12, Mgal 200m. 10, Red gum 6, Strontium Carbonate 11, Copper oxide 6, Dextrin 4.The only changes i made was1. replace Red Gum and Dextrin with Phenolic resin.2. i came up short on Copper oxide, so i finished with Black copper oxide.What i wound up with is another white.This was not a star it was just mixed comp. Like i said i am no chemist, but it looks like Mgal and Phenolic resin don't mix.Other than that i don't know why it washed out.
Mumbles Posted November 7, 2016 Posted November 7, 2016 I don't know that I'd get too down on the formula yet. A lot of stars will not burn right without being bound or at least maybe pressed into a lance tube. Oxygen is bad news for delicate colors, especially with metals around. We ideally want to keep the emitting species as the chlorides which give the desired emission bands, and not as oxides which are often other colors. In fact, copper actually turns somewhat red with oxygen around and likely would ruin the positive effect it has on this particular formula. Additionally it is desirable to keep species from the MgAl also devoid of oxygen, which can turn them into very bright white emitters, which is likely what's going on here. From a practical point of view, testing as a powder generally does not allow one to get as far back to better view the flame view. Did you do 1:1 replacements of the red gum and dextrin for phenolic resin? Phenolic resin has been found to have a higher fuel value than red gum by about 20%. I just saw Jim Widmann recommend that you should replace 1 part red gum with 0.82 parts phenolic resin. I don't have a value on hand for dextrin, but it generally doesn't seem to make a lot of difference when included or not based on what I've read. Maybe replacing the red gum 1:1 and not making any correction for the dextrin would be a comfortable compromise. That formula is designed to be used with black copper oxide. I'm not sure if you may have just misspoke, but wanted to clarify. I bet copper oxychloride or carbonate would probably work alright in a pinch. It works fine in some blues and purples which bear some similarities to this formula. It's actually a violet or magenta formula that was carefully partially washed out. If you need any help or advice I'm always a private message or reply away. 1
dynomike1 Posted November 8, 2016 Author Posted November 8, 2016 THANKS Mumbles I did replace the red gum 1:1 and just deleted the dextrin. I did miss quote, it was Copper carbonate and i finished with Black copper oxide. You might be right about bounding the stars, i will try that tomorrow. The funny thing about this is the first time i burnt some after i shook it up in a bag, it was like a washed out magneta. After that i screened the comp that's when it turned on me. Come to think of it there was a lot of red like grains lying there where i burnt the comp. I have plenty black copper oxide from when i was making serpents. I guess i am out of carbonate.
OldMarine Posted November 8, 2016 Posted November 8, 2016 I've been keeping up with the threads on the phenolic and so far the consensus is that dextrin should be replaced at .5-1 with phenolic. This is one of the most interesting subjects I've read lately.
braddsn Posted November 8, 2016 Posted November 8, 2016 Mike, I am not sure what happened to your formula... in my experience, 'most' of the time, my comp in powder form burns the same color as the bound star. This is especially true with 'colors'. With charcoal stars and glitters, it's a different story. I don't know why it's burning white.. but here is one piece of advice.. the pink formula that you used is the same one I used to use. It's 'ok' at best (in my opinion). The pink that I listed in the other thread (the spanish one) is much better. You might want to give it a try. When I used the one you just listed before, I always ended up with a washed-out pink, almost a whitish pink, and that's why I ditched it. Some ppl like the washed out look, so it's ok.. but I like a deeper pink. Also, it might have something to do with using copper carbonate. I have no experience with copper carbonate.. I only use black copper oxide and have great luck with it. FWIW, I rolled every single one of my pastel colors this year with phenolic in the place of red gum (1:1), and all of the colors are just as deep and beautiful as they have always been. The only differences I notice are 1)They burn slightly faster, and 2)They are easier to light. Color wise, they are exactly the same, no wash-out.
dynomike1 Posted November 8, 2016 Author Posted November 8, 2016 Thanks Brad Fuscia is next. After i pump some of these others.
Zumber Posted November 9, 2016 Posted November 9, 2016 Why to use potassium nitrate in composition???I would have probably omitted it.
Mumbles Posted November 9, 2016 Posted November 9, 2016 Why to use potassium nitrate in composition???I would have probably omitted it. It's a white body emitter. Without it, it's more of a magenta or violet star kind of like the spanish fuscia. With it, you intentionally wash it out slightly and turn it into a vibrant warm pink.
dynomike1 Posted November 9, 2016 Author Posted November 9, 2016 I used it because that's what the formula called for. I guess the designer would have to answer that.
wildcherryxoxo Posted November 11, 2016 Posted November 11, 2016 In my experience the pink listed is quite excellent! I really love it with copper oxychloride instead of copper oxide.
dynomike1 Posted November 11, 2016 Author Posted November 11, 2016 (edited) There was a typo. It was copper carbonate instead of copper oxide. But it still worked after i made the stars. The last batch i made was with copper oxychloride. Looks better. It and Fuscia both have there place. Edited November 11, 2016 by dynomike1
braddsn Posted November 12, 2016 Posted November 12, 2016 IT has been a couple years since I have tried that pink comp. I think I am gonna try it again. The fuscia is awesome, but leans somewhat towards a purple. From what I remember, that pink is actually PINK. I remember pyro science blue and that pink comp being a little washed out for my taste, but the more I think about it, a true PINK is supposed to be pale. Well, looks like I am rolling some pink this weekend.
dynomike1 Posted November 12, 2016 Author Posted November 12, 2016 (edited) I pumped some of those day before yesterday and tested while ago, and they were pink enough for me .I also used Copper oxychloride. I think that made a difference. It appeared to be a shade or two darker than chris. You have to watch them Brad, a 1/2" star with Phenolic resin burns around 2.5 sec. Edited November 12, 2016 by dynomike1
greenlight Posted November 16, 2016 Posted November 16, 2016 (edited) I have two pink formula's I have tested over the past week. The first one is quite a light pink and is as follows: Potassium chlorate: 27.5%Strontium nitrate : 5.0%PVC powder : 5.0%Copper oxide : 2.5%Magnalium : 2.5%Dextrin : 7.5% The second is about the brightest magenta/bright pink I have made: Potassium perchlorate : 5.0%Strontium nitrate : 20.0%Magnalium : 5.0%Copper oxide : 7.5%Sulfur : 2.5%Charcoal (powdered) : 2.5%Parlon : 10.0%Dextrin : 2.5% On the left is a few stars of the first composition at the top of a crackling mine and second is the second bright magenta composition Edited November 16, 2016 by greenlight
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