Fire-Man Posted January 13, 2008 Share Posted January 13, 2008 This is my first shell, wasn't perfect, but my friends seemed to be excited. Definitely not the biggest shell, way to much lift, nice thump but a weak break. http://www.apcforum.net/files/PHOT0076.JPGhttp://www.apcforum.net/files/PHOT0077.JPGhttp://www.apcforum.net/files/PHOT0078.JPGBasically it was plastic hemis from pyrocreations, green blue and glitter formulas from Tom Perigins Book on Practical Pyrotechnics. I stacked the stars on the side but I guess I didn't pack them in tight enough. The red were from a defective shell that cracked open after landing on the pavement. I used BP with a tiny bit of flash to break. If it didn't go so high it might of looked better. Shell was bonded with xylene. I wrapped it in making tape because my kraft paper tape hasn't come in yet. Used 5.2 grams of 2fg lift for a 34 gram load. I'm guessing that was supposed to be right?? Now I'm on to my first 3", brilliant white star formula shell with a Ti- break. I bought all the different sizes of plastic hemis possible so I will step up after every success. Here's the video 1-3/4" Shell. Green, Blue, Red, Glitter stars, rolled+primed stars Link to comment Share on other sites More sharing options...
Xtreme Pyro Posted February 5, 2008 Share Posted February 5, 2008 This is my first shell, wasn't perfect, but my friends seemed to be excited. Definitely not the biggest shell, way to much lift, nice thump but a weak break. http://www.apcforum.net/files/PHOT0076.JPGhttp://www.apcforum.net/files/PHOT0077.JPGhttp://www.apcforum.net/files/PHOT0078.JPGBasically it was plastic hemis from pyrocreations, green blue and glitter formulas from Tom Perigins Book on Practical Pyrotechnics. I stacked the stars on the side but I guess I didn't pack them in tight enough. The red were from a defective shell that cracked open after landing on the pavement. I used BP with a tiny bit of flash to break. If it didn't go so high it might of looked better. Shell was bonded with xylene. I wrapped it in making tape because my kraft paper tape hasn't come in yet. Used 5.2 grams of 2fg lift for a 34 gram load. I'm guessing that was supposed to be right?? Now I'm on to my first 3", brilliant white star formula shell with a Ti- break. I bought all the different sizes of plastic hemis possible so I will step up after every success. Here's the video 1-3/4" Shell. Green, Blue, Red, Glitter stars, rolled+primed starsNice lookin shell for your first one, but i am unable to watch the video, for some reason it doesen't work for me. I am using windows media player. I can hear the sounds but cant see anything. Link to comment Share on other sites More sharing options...
GalFisk Posted February 5, 2008 Share Posted February 5, 2008 Nice lookin shell for your first one, but i am unable to watch the video, for some reason it doesen't work for me. I am using windows media player. I can hear the sounds but cant see anything. It's xvid, you can find a codec here: http://www.free-codecs.com/download/Koepi_XviD.htmA good deal better for a first shell than mine.I've heard the correct amount of lift is either 1/10 or 1/16 of the shell weight. I use 1/10 of benzolift for my small shells (haven't gone larger than 2" yet). Link to comment Share on other sites More sharing options...
Fire-Man Posted February 10, 2008 Author Share Posted February 10, 2008 I've heard the correct amount of lift is either 1/10 or 1/16 of the shell. what would be the ratio for 2fg? Link to comment Share on other sites More sharing options...
TheSidewinder Posted February 10, 2008 Share Posted February 10, 2008 Fire-Man, I've used 2Fg as lift for my 3 and 4 inch cannnisters. If your shell weighs less than a pound, you'll still use nearly an ounce. I needed 25-28 grams lift for all of them, and their weights ranged from slightly less than a half-pound to just over a pound. But this is just a starting point. You *WILL* have to experiment a bit. Once you get above a pound, the formula is 1/16 (1 ounce per pound of shell). Above a certain diameter, it's 1 ounce per pound for the first "X" pounds, then 1/2 ounce per pound for the remaining weight. This is only a rough formula. The "density" of the shell plays a part, too. A 6-inch "shell of shells" will probably need less lift than a 6" Peony or Chrysanthemum, for example. Once you "get it just right", be sure and record the details somewhere, so when you get old and gray like me you won't HAVE to remember exactly how much lift your "Shell X" needs. Link to comment Share on other sites More sharing options...
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