dagabu Posted April 22, 2011 Posted April 22, 2011 Good morning everyone, I have a brand new 1-1/4" cavity pump that I want to try out this weekend and would like some ideas for the outer part (long burning portion) and the inside part (the end of the comet). I have had the idea to use C-6 for the initial burn and red metallic fueled end. Go ahead and post your preferences here, I would like a few to choose from. -dag
Ralph Posted April 22, 2011 Posted April 22, 2011 Good morning everyone, I have a brand new 1-1/4" cavity pump that I want to try out this weekend and would like some ideas for the outer part (long burning portion) and the inside part (the end of the comet). I have had the idea to use C-6 for the initial burn and red metallic fueled end. Go ahead and post your preferences here, I would like a few to choose from. -dag when making ghetto carbity commets Ive allways used a smaller red or green star and an out glitter (RG#1 usually)
dagabu Posted April 22, 2011 Author Posted April 22, 2011 when making ghetto carbity commets Ive allways used a smaller red or green star and an out glitter (RG#1 usually) RG#1? Really? Its my favorite glitter so far too. -dag
TheEskimo Posted April 22, 2011 Posted April 22, 2011 I wonder if you could place a strobe on the outside, and go-getter on the inside? Imagine strobes just shooting all over the place...
dagabu Posted April 22, 2011 Author Posted April 22, 2011 Why not? Press 1 ID of strobe into one end of the tube and fill the rest with go-getter mix. They are both AP based so no reaction should take place. Prime with a Perc prime on both ends and you should be good to go.... getter I have NOT made these this way so consider it experimental.
pyrogeorge Posted April 23, 2011 Posted April 23, 2011 dagabu we waiting a photo of your cavity stars
dan999ification Posted April 23, 2011 Posted April 23, 2011 dagabu we waiting a photo of your cavity stars yes. and i would like to know the purpose of the cavity?.as far as effect goes ive always been a fan of tigertail/orange comps changing to blue im sure there's plenty of options.dan
Ralph Posted April 23, 2011 Posted April 23, 2011 yes. and i would like to know the purpose of the cavity?.as far as effect goes ive always been a fan of tigertail/orange comps changing to blue im sure there's plenty of options.dan cavity stars are usually used to have 2 different effects going at the same time (or the cavity is left open to increase the burn front and therefore burn rate of the star giving a more dence tail) its a good way of achieving tailed colours usually the tail comp would make up the outer part of the star and than have the iner colour comp smeared /poored/pressed in though sometimes when a brighter colour and less of a tail is deseried people will do the opposite
dagabu Posted April 23, 2011 Author Posted April 23, 2011 (edited) dagabu we waiting a photo of your cavity stars Well, you guys gave me a few good ideas and I chose a version of RG#1 with a slightly faster burning comp for the body of the star (comet) and Red Lacquer for the insert. After speaking with a few more experienced pyros, I was told that I have to "butter" a second comp into the cavity in order to get good mechanical connection between the two comps. I will be pasting this comet in so that it is color changing rather then a dual tone comet. I made this decision because of the duration of the burn so that when launched from a 3# rocket, they would have more time to fall before burning out. If all goes well, I will be building a 6" canister shell for PGI with these comets but without pasting them in. Here is one of my cavity stars (for you pyrogeorge) and the pump. http://www.pyrobin.com/files/100_2145.jpg Edited April 23, 2011 by dagabu
AdmiralDonSnider Posted June 10, 2012 Posted June 10, 2012 Dagabu, I´d love to hear combinations that worked well for you in those comets. I have a similar 9/8" pump from Wolter and found that the combinations are very hard to get right in terms of burn duration and, especially, brightness. The streamer easily overpowers the waver portion and appears washed out.
dagabu Posted June 11, 2012 Author Posted June 11, 2012 Dagabu, I´d love to hear combinations that worked well for you in those comets. I have a similar 9/8" pump from Wolter and found that the combinations are very hard to get right in terms of burn duration and, especially, brightness. The streamer easily overpowers the waver portion and appears washed out. I am sorry but I havent finished a single one yet, the base comet took a long time to dry and then it was fireworks display season which eats up most of my build time. I am hoping to get at least one shell up for PGI since we now have legal transportation through the PGI for homemade pyrotechnics -dag
mabuse00 Posted November 17, 2020 Posted November 17, 2020 Dagabu, I´d love to hear combinations that worked well for you in those comets. This is really old, but since I meanwhile own a very nice cavity pump myself and the question applies,I hereby dare to do some gravedigging.The pump is 20mm and the proportions are similar to what Wolter once offeredIf you guys would share some some ideas to try out, please write about them. A bright star surrounded by a glitter seems like a typical idea, or a blue star surrounded by a faint charcoal dust... Pump the hull, butter the core in and - maybe press it again to add a bottom rather than pasting the thing?How about the expansion problem, did you encounter cracking issues?
snapper Posted November 18, 2020 Posted November 18, 2020 try a charcoal star with a zinc star as the core, some like to bind and some like to press the two together. the main comp should be faster and the second I would suggest a more difficult to ignite or lower critical wind velocity comp. a little wrap over the end of the second comp would be suggested unless you want both lit at the same time or you can go single comp for a sort of lazy go getter.
mabuse00 Posted December 1, 2020 Posted December 1, 2020 Granite stars are a good idea, thanks for mentioning.Unfortunately did not make a single test yet...
pyrojig Posted December 13, 2020 Posted December 13, 2020 I'd try a parlon or go getter comp that you have to paste into the cavity. I believe it would be similar to a married comet, but easier .I have considered something also along these lines , but never put to practice
Carbon796 Posted December 13, 2020 Posted December 13, 2020 (edited) The back, cavity side, should be pasted in. It should start as a single effect. Then transition to an additional effect. Like color to a bright streamer. Or gltter to color. If you dont paste the back side in. It's common for the two comps to separate mid air, if they are not bonded well. The taper of the tooling helps this. As well as the fact, that the buttered in comp usually shrinks back as it dries. If you want a simultaneous two effect star, married comets are easier and more reliable. Edited December 14, 2020 by Carbon796
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