dangerousamateur Posted August 15, 2012 Posted August 15, 2012 Hi, here's some question for the whistle pros: The diameter of the whistle spindle seems to have an effect on the burning behaviour. More area - more thrust. On the other hand, tighter "nozzle" - more thrust. Thing is, when I use a BP tooling with a rather short spindle, made for short tubes, with whistle fuel, what will happen? It's spindle is little shorter then that of a long winded screamer, but the "nozzle" is 6,5mm, compared to 8,5mm for the screamer. What do you expect this to do? Hopeless endeavor or worth a try? Will this rather generate more thrust and explode?
a_bab Posted August 15, 2012 Posted August 15, 2012 (edited) There are so many factors involving whistle rockets such as fuel quality (the most important - seems to be the main problem), where you light up the fuel (a visco inside the core will likely CATO the engine), tube strenght etc. Generally speaking, a BP tooling will be useless for whistle as the spindle is way too long. The spindle diameter is best at 1/3 of the engine diam, and the max length seems to be around 2x-2,5x engine diam (for pusher). Anything more will require tame fuel (LWS) or it will make more noise then work if shorter. The taper is not that important; I've seen from almost no taper (spindle made from rods) to max (so the spindle is a cone). The primary role of the taper is to help extracting the spindle, since pressing the rocket between 6000-9000 psi will grab it really well, depending on the fuel. Edited August 15, 2012 by a_bab
dagabu Posted August 20, 2012 Posted August 20, 2012 The spindle diameter is best at 1/3 of the engine diam, and the max length seems to be around 2x-2,5x engine diam (for pusher). Anything more will require tame fuel (LWS) or it will make more noise then work if shorter. In my experiences, Universal Tooling works well for whistle rockets and the spindle is around X6 the ID. I am going to guess you are talking about Sodium Salicylate and not Benzoates. -dag
dangerousamateur Posted August 22, 2012 Author Posted August 22, 2012 If it's too fast, one can always add some charcoal ec. to slow it down, that is not my problem.I'll try it when I get my press.
a_bab Posted August 22, 2012 Posted August 22, 2012 Dag, I'm not talking about sally here. I only use Na benz. I haven't tested the UT but anything over spindle length= 3 x ID will CATO on me. But then again, I incorporate my whistle very well plus I use the purest KP you can get (think lab grade). Fuel consistency in whistle is really a poblem, especially giving the large number of KP sorts you can get in USA, and the differences in incorporation work. This is zhat gave lots of spindles etc.
dagabu Posted August 23, 2012 Posted August 23, 2012 Dag, I'm not talking about sally here. I only use Na benz. I haven't tested the UT but anything over spindle length= 3 x ID will CATO on me. But then again, I incorporate my whistle very well plus I use the purest KP you can get (think lab grade). Fuel consistency in whistle is really a poblem, especially giving the large number of KP sorts you can get in USA, and the differences in incorporation work. This is zhat gave lots of spindles etc. Yup, you have better KP then most of do then, I can do benzo all the way up my UH spindle and not pop it. The comp is very well integrated too. -dag
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