BlueComet24 Posted May 30, 2016 Share Posted May 30, 2016 Does anyone know the linear burn rate of C6? Specifically, moistened and hand-rammed into 1x1" comets (if that makes much of a difference).Thanks.-Blue Link to comment Share on other sites More sharing options...
ddewees Posted May 30, 2016 Share Posted May 30, 2016 It burns pretty fast blue... almost as fast as black powder. I'd estimate about three seconds per inch.. but you may want to test for yourself. Link to comment Share on other sites More sharing options...
PhoenixRising Posted May 30, 2016 Share Posted May 30, 2016 That's probably going to vary depending on what kind of charcoal you use and how long it's milled for. At least I "think" that's how it works. Hand ramming is going to add another uncontrolled variable. A press would be needed to achieve the same pressure each time to get some kind of baseline measurement. Link to comment Share on other sites More sharing options...
Mumbles Posted May 30, 2016 Share Posted May 30, 2016 You can comfortably plan on 2.5 to 3 seconds. I don't have a lot of experience with C6 specifically, but I do make a lot of spider stars. These typically are very close in formula to C6, just with a touch less charcoal (~29%) and a bit more sulfur (~9%). If you mill it like BP, and use a hot charcoal, that burn time would probably be closer to 2 seconds or a touch less. I typically use commercial airfloat, and only mill for about 20-30 min to pulverize everything. You can test burn them on the ground, but out of a star gun or mine will be most accurate since charcoal streamers rely on atmospheric oxygen and moving through the air for part of the reaction. Link to comment Share on other sites More sharing options...
BlueComet24 Posted May 30, 2016 Author Share Posted May 30, 2016 Thanks, guys.I think this batch will burn slower because I was lazy and just used commercial airfloat and didn't ball mill it. That's fine; I like longer hang times on comets, and I figured it might be slowed down to more like milled C8.I can't test this batch out of a star gun because I made it all into comets (100g perfectly made 7 1x1" and 1 1x.75" comets, plus some dust/crumbs all over) and I don't want to "waste" one.Mumbles, couldn't C6 be used as a spider star? It's only a couple percents off from Ofca's Gold Spiderweb. As I understand it, spider shells are just chrysanthemum shells that break really hard (boosted, maybe entirely flash breaks on smaller shells?) and use fast-burning stars so that the stars don't have curved flight paths, and instead go straight outward. Link to comment Share on other sites More sharing options...
Mumbles Posted May 31, 2016 Share Posted May 31, 2016 You can absolutely use C6 interchangably with spider stars. I happen to like a formula I got from Mike Swisher that doesn't require any milling. It has a touch of lampblack, but otherwise very similar to C6. Chrysanthemum shells are ball shells while spider shells are cylinder shells, but otherwise are very similar. They're both designed to be hard broken, charcoal tailed stars, with little to no droop. It's no surprise that the two different shell types developed almost identical formulas. Spider shells specifically look nice fired in volleys, where the tails overlap. The shells do look like spider legs, but it's actually this overlapping pattern simulating a spider web that the shells get their name from. What are you looking to do with the stars/comets? Link to comment Share on other sites More sharing options...
MeowMix Posted May 31, 2016 Share Posted May 31, 2016 I happen to like a formula I got from Mike Swisher that doesn't require any milling. It has a touch of lampblack, but otherwise very similar to C6. Can you share this formula? Link to comment Share on other sites More sharing options...
BlueComet24 Posted May 31, 2016 Author Share Posted May 31, 2016 I haven't got any lampblack, so I've avoided comps containing it so far. Could I just substitute charcoal or graphite instead? I'm just going to fire these comets individually, or possibly in a cake. Link to comment Share on other sites More sharing options...
Mumbles Posted May 31, 2016 Share Posted May 31, 2016 Gladly. Mike works with commercial sized batches, so the formula is given in pounds, but I included approximate percentages. The lampblack is optional, but see the first link for a description as to why it is used. Use charcoal in it's place if you do not have any. It's a very small amount and the effect is subtle, but I like the extra little bit it adds. KNO3 - 18 (55.4%)Charcoal - 9 (27.7%)Sulfur - 3 (9.2%)Dextrin - 2 (6.2%)Lampblack - 0.5 (1.5%) From: http://groups.google.com/group/rec.pyrotechnics/browse_thread/thread/a960c89228f22afa/c5908a0de01b49ba?hl=en&q=mike+swisher+spider+web+lampblack#c5908a0de01b49ba He gave out a very similar formula another time as well. http://groups.google.com/group/rec.pyrotechnics/browse_thread/thread/765b7bf335be3cd3/5f7c2c174d14ed3a?hl=en&q=mike+swisher+spider+web+lampblack#5f7c2c174d14ed3a Edit: Here's a video of a shell I made containing the above stars. 1/4" cut stars in the inserts, and 1" pressed comets in the sfera. 1 Link to comment Share on other sites More sharing options...
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