garyrapp55 Posted June 19, 2011 Posted June 19, 2011 (edited) I'm getting ready to make some blue stars, the formula is ammonium perchlorate70, red gum10, copper carbonate10, dextrin5, charcoal10. Aside from gloves and my dust mask, are there any other safety precautions I'm not mentioning, aside from the obvious (no open flames etc.)? Are there any buffers or special primes for these types of stars?Gary Edited June 19, 2011 by garyrapp55
Seymour Posted June 20, 2011 Posted June 20, 2011 You are going to need purely Potassium perchlorate primes for this one, since K nitrate will cause Ammonium nitrate to form, and they'll never dry. KP burst charge, or similar should be an effective alternative to meal primes. The main safety issue that comes to mind is not one of toxicity, but the Ammonium salts and chlorates incompatability. Being one of the most serious incompatabilities(worse than chlorate-sulfur), be careful to keep the two well apart.
superstring Posted June 20, 2011 Posted June 20, 2011 I've had much experience with AP stars, blue in particular. The KP burst is a must, and make it a little on the heavy side. Top off the KP by then a dusting of BP. You should dry in between primes. The heavier the KP prime the better as these stars are shock and friction sensitive. DO NOT add metal to the blue, like Ti or MgAL. a very small piece struck with a hammer will make a very LOUD report. I can'rt even imagine what it'd be like to have a shell det in a tube with this mix.It DOES make a very nice blue though. Do not use AP stars ever in mines! You are going to need purely Potassium perchlorate primes for this one, since K nitrate will cause Ammonium nitrate to form, and they'll never dry. KP burst charge, or similar should be an effective alternative to meal primes. The main safety issue that comes to mind is not one of toxicity, but the Ammonium salts and chlorates incompatability. Being one of the most serious incompatabilities(worse than chlorate-sulfur), be careful to keep the two well apart.
garyrapp55 Posted June 20, 2011 Author Posted June 20, 2011 (edited) Why can't AP stars be used in mines? Does the formula I showed sound good, can you guys reccomend a better one? Edited June 20, 2011 by garyrapp55
Seymour Posted June 23, 2011 Posted June 23, 2011 I've had much experience with AP stars, blue in particular. The KP burst is a must, and make it a little on the heavy side. Top off the KP by then a dusting of BP. You should dry in between primes. The heavier the KP prime the better as these stars are shock and friction sensitive. DO NOT add metal to the blue, like Ti or MgAL. a very small piece struck with a hammer will make a very LOUD report. I can'rt even imagine what it'd be like to have a shell det in a tube with this mix.It DOES make a very nice blue though. Do not use AP stars ever in mines! Ammonium perchlorate stars are certainly quite sensitive (more like Potassium chlorate than Potassium perchlorate in this regard), but I don't think you need to go to quite the extremes that you are to be safe. While I would not be surprised if MgAl and Ti do sensitise Ammonium perchlorate colours, you are still going to get a good crack from AP mixes without them, and, with a harder wack, most Potassium perchlorate and chlorate mixes. Many formulas that I've used, and seen on reputable sources use Ammonium perchlorate and Magnalium, or titanium, so I'm not entirely sure where the source of the information that you have is. I also cannot think why there could be any reason not to use them in mines. In all factors, a mine is a much gentler experience for the stars than in a shell. I would also hesitate to add a final step of BP over the KP prime if a water activated binder is to be used for it and the KP prime, because if it's damp, it's likely to diffuse through. Does the formula I showed sound good, can you guys reccomend a better one? I have not tried that particular formula, so I cannot really say if it's good. Certainly many AP blues are good, and there are some very good ones are out there. However many have rather more exotic chemicals than the one you posted. My suggestion is to see what formulas you can find that have the chemicals you have, and make small test batches. Make a few stars, and get someone to light them fifty meters away, and if you like one particular one, go with it.
californiapyro Posted June 24, 2011 Posted June 24, 2011 (edited) ive tried that formula, very cool. More of a purple-blue though, with a charcoal tail. if you don't want a tail you can omit the charcoal. if you do, use 80 mesh. For this formula, I recommend omitting the dextrin and binding with alcohol, as the red gum acts as a binder. If you want a straight up AP blue, try 75 AP 15 CuO 15 shellac. if you have a cost issue, you can substitute the shellac for 10 parts hexamine. good luck! Edited June 24, 2011 by californiapyro
Mumbles Posted June 24, 2011 Posted June 24, 2011 That's Bruce Snowden's formula from Pyrotechnica I. Unfortunately, it's one of the issues I don't have. I often see it recommended to use all 80 mesh, or a few parts airfloat and the rest 80 mesh. It is supposed to enhance ignition. Again, I don't have the journal to reference, but I often see annotations saying to wet it with alcohol despite it having dextrin in it. Bruce Snowden is an interesting guy if you want to look him up on google. He was a professional fat man.
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