Uarbor Posted July 31, 2021 Posted July 31, 2021 (edited) So I have been studying the writings of Steve La Duke and I have taken a particular interest in the long-winded screamer because I have the universal hybrid tooling and I'm about to get into whistle. My question is why does he make the switch from sali whistle to benzo whistle halfway up in the core? I mean I do understand that's what keeps it from exploding but why not just use benzo the whole way? Edited July 31, 2021 by Uarbor
justvisiting Posted July 31, 2021 Posted July 31, 2021 You need the initial thrust and burn speed of the sali whistle to get the rocket going and achieve some height. Then the much slower and less powerful benzo whistle takes over and keeps the rocket going much higher (and slower) so that the rocket is still in the air for the entire duration of the burning of the delay. The slowed benzoate whistle is not your regular benzoate whistle. Regular whistle would burn too fast to give the extremely long air time desired. I was able to match but not beat Steve's record time of 23 seconds, but I think he's at 25 now anyway. When I experimented with those, I had a problem with the slow whistle extinguishing at the interface between increments. Adding a bit of charcoal solved that issue. 23 seconds is a really long time for a rocket to be in the air, and it's hard to do. 1
Uarbor Posted July 31, 2021 Author Posted July 31, 2021 (edited) You need the initial thrust and burn speed of the sali whistle to get the rocket going and achieve some height. Then the much slower and less powerful benzo whistle takes over and keeps the rocket going much higher (and slower) so that the rocket is still in the air for the entire duration of the burning of the delay. The slowed benzoate whistle is not your regular benzoate whistle. Regular whistle would burn too fast to give the extremely long air time desired. I was able to match but not beat Steve's record time of 23 seconds, but I think he's at 25 now anyway. When I experimented with those, I had a problem with the slow whistle extinguishing at the interface between increments. Adding a bit of charcoal solved that issue. 23 seconds is a really long time for a rocket to be in the air, and it's hard to do. thanks for the info. You clearly know a lot about it. I am starting to search out my ingredients for some whistle for my Universal spindle. I ordered some potassium benzoate because I heard it was less Hydro scopic. Of course I'm going to start out with straight benzo rocket on my first attempts. Do you think using red iron oxide is it going to get this thing off the pad fast enough for Reliable flight? I really just want to make a whistle rocket that flies and is not on the verge of exploding its first time out. And I will work my way up into more advanced things from there. Right now I'm still on black powder. Which I am getting pretty reliable with. From there I think I'm just going to use black powder around a spindle and benzo delay as my first introduction to whistle. Please let me know if you see anything wrong with these ideas Edited July 31, 2021 by Uarbor
justvisiting Posted July 31, 2021 Posted July 31, 2021 I've read that about potassium benzoate too. If you live in a dry climate, it might not matter much which benzoate you use. People compare 'benny' and 'sally' whistle comps as if they are two separate and distinct things. In reality, some benzoate comps rival the standard 'Laduke #2' salicylate comp, which is 76-23-1-2.5, with red iron oxide being the 1. 70-30-1-3 is a typical benzoate whistle comp for a long spindle like you have, and the 1 is red iron oxide. A really fast benzoate whistle with a lot more zip is 76-23-1-3, with the 1 being copper oxychloride. No need to start with that comp, I was just using it to show how different benzoate whistle comps can be. Your idea of using whistle as the delay/bulkhead in a BP rocket will work just fine. It's just a rocket that whistles, rather than a whistle rocket. Before changing from BP to whistle, you might make an increment of both comps mixed together, just to make sure the BP lights the whistle. And I wouldn't use the slowed whistle formula for the LWS in the rocket either, or you might get a gopher hunter Steve Laduke uses Vaseline in lacquer thinner in all his whistle. I use wax in naphtha in all mine. Ben Smith uses a LOT of Vaseline in his whistle, which I found to be undesirable. Too much phlegmatizer makes the comp too squishy, in my limited experience with it.
ronmoper76 Posted August 4, 2021 Posted August 4, 2021 He is right,its the type of benzoate fuel. If you stack 76/23/1 Benz/oxychloride on top of Sali it will blow sky high,they are almost the same thrust if you look at creagans tests.Its a weaker Benz formula,personally I see no advantages to sali,I pay 4.00lb for sodium Benz and throw some oxychloride in it and it's wicked powerful and works on long spindles. To each there own
dagabu Posted August 20, 2021 Posted August 20, 2021 He is right,its the type of benzoate fuel. If you stack 76/23/1 Benz/oxychloride on top of Sali it will blow sky high,they are almost the same thrust if you look at creagans tests.Its a weaker Benz formula,personally I see no advantages to sali,I pay 4.00lb for sodium Benz and throw some oxychloride in it and it's wicked powerful and works on long spindles. To each there own I too just use Benzoate whistle, I dont own any Sali. Using Copper Oxychloride for the catalyst in Benzo fuel, Danny got 2600 grams of thrust vs 2400 grams of thrust from Sali. The trick is in the catalyst.
dangerousamateur Posted August 21, 2021 Posted August 21, 2021 The slowed benzoate whistle is not your regular benzoate whistleCan somebody shed some light onto this?If it's not regular 70/30 benzoate fuel - what is it than?Does it have some retardant added? What also interests me is how to get this slow fuel to burn slowly but to make as much noise as possible per burned mass.
dagabu Posted August 21, 2021 Posted August 21, 2021 Can somebody shed some light onto this?If it's not regular 70/30 benzoate fuel - what is it than?Does it have some retardant added? What also interests me is how to get this slow fuel to burn slowly but to make as much noise as possible per burned mass. You can use less Perc, add more phlegmatizer, add more catalyst than needed, many ways to retard the burn and get different noises from Benzo.
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