Zmuro Posted December 17, 2013 Posted December 17, 2013 I'm building 8" canister shell with five 3" salutes (100g FP in each) and I have a question about salute delay. The first salute will go off 2s after bursting and the others will follow in 1s intervals, therefore the last salute will go off 7s after the burst. Do you think that I should use smaller delays? I don't want salutes to go off on the ground obviously...
fredhappy Posted December 17, 2013 Posted December 17, 2013 #zmuro : don't worry about the salutes hitting the ground. I'd use a 2 second delay with a somewhat strong lift charge for the shell you are describing. The speed of rising of the 8" main shell will give more than enough momentum to the salutes to go off at a correct height. To be honest...I'd opt for 1.6 seconds, but 2 seconds on the 8"mothershell is enough delay. I build 8"stutatas with 14x2.5"inserts. The main shell is timed at 1.2 seconds, and the fourteen inserts are set to go off in a timeframe of about 4 seconds...believe me, they have sufficient height even with a very short delay of 1.2 seconds. Please film your shell and let me know how it went... best of luck and have fun. best fred
Zmuro Posted December 17, 2013 Author Posted December 17, 2013 Fred, thanks for answer but I'm thinking to give the main shell the delay of 3-3,5s (to get to a proper height) and 2s after the main shell bursts the first salute will go off. I will also put some willow or glitter stars on top of salutes.
psyco_1322 Posted December 18, 2013 Posted December 18, 2013 If you break the shell while it's still moving upwards pretty good, that will allow the inserts to continue to travel up and out. If you break the shell somewhere around it's apogee, then the inserts will spread out and fall back towards the ground. That shell had a 1/2" powder charge in the initial spolette, which is about 1.3 secs for my powder. The gun we shot it from was a bit on the short side, and contributed to the underlifting of the shell. The the second break had a very tight fitting ring of 6 larger reports that sort-of contained the break and shit everything out the ends of that break. The BS could have been timed a bit less, but I think it was mostly a difference in spolette burn times and the time fused salutes.
fredhappy Posted December 19, 2013 Posted December 19, 2013 (edited) psycho: that is one helluva shell!, excelent work sir! zmuro: please observe this previous 8"stutata of mine. https://www.youtube.com/watch?v=bVxt97M5iOA The main shell was timed at 1.2 seconds. Inserts had a total timeframe of 4 seconds and as you can observe, the inserts still had plenty of momentum to go off at a proper height. It is just a matter of preference, but I likemy stutatas breaking low. The safety issue is more of a psychological issue then it is a trulu dangerous..I am not advocating to simply take a gamble and assume the height will be ok, I am assuming you can make reliable lift that performs the same every time. I do use a fair amount of lift for these stutatas. I ve made quite a few of these 8"stutatas and the ones I liked best were the ones with short mainshell timings...1.2 seconds will do nicely, 1.6 seconds is already overlifting it too much for my taste. best fred edit: sideglance, you were right ..I ve fixed it, sorry for the inconvenience Edited December 19, 2013 by fredhappy
psyco_1322 Posted December 19, 2013 Posted December 19, 2013 Thanks Fred, your shell was quite nice as well. Where the stars in the inserts blue changing to the silver?
fredhappy Posted December 19, 2013 Posted December 19, 2013 psycho: no, 7x2.5" pyroscience blue and 7x2.5"orange on the first 8"er. I'd timed them to go off in 2 groups with a second or so between the groups. best fred
psyco_1322 Posted December 21, 2013 Posted December 21, 2013 psycho: no, 7x2.5" pyroscience blue and 7x2.5"orange on the first 8"er. I'd timed them to go off in 2 groups with a second or so between the groups. best fred I think you posted the wrong link. That shell is not blue and orange, but I think I recall watching that video. That one looks like either color changing stars or blue with Ti in it, hard to tell.
Zmuro Posted December 21, 2013 Author Posted December 21, 2013 Thanks for all replays. Then I will use 1,6 s delay and glitter stars. Willow diadem would burn to the ground if I don't break this shell at apogee.
fredhappy Posted December 21, 2013 Posted December 21, 2013 psycho: you are right, so sorry for all the misunderstanding, I will pay more attention to my post next time The stutata was basically the same, with the inserts going off in 2 groups with a 1.5 second interval. I had used a blue formulae with added FeTi and then the silver streamers. zmuro: 1.6 seconds sounds fine and I predict your shell will break at an ok height. I am looking forward to the footage.
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