nater Posted May 11, 2014 Posted May 11, 2014 I received a set of tooling with interchangeable taper pins as spindles. This allows you to tailor the spindle to the fuel or make several different cored devices with the same set of tooling. The first test I performed as comparing how the catalyst used in whistle fuel effects sound and thrust. Dan Cregan has already performed extensive testing on the subject, and I have no intention of repeating all of his efforts. I only wanted to see the results for myself with compositions and tooling that I use. Each whistle was 1" ID pressed with a 1" tall core around a 1/4" stainless steel taper pin. Each fuel was standard 76/23/1 Sodium Benzoate Whistle with 3% mineral oil dispersed in acetone. The only changes were comparing copper oxychloride and red iron oxide as the catalyst. Each batch used air milled Sodium Benzoate with the catalyst screen in, mixed in a baggie with the acetone / mineral oil and then the milled perc added. The mix was kneaded thoroughly before being granulated and dried. As expected from reading Dan Creagan's notes, several of us thought the whistle with the red iron oxide was louder. As you can tell from the video, the difference is minimal. The whistle with copper oxychloride did have more thrust - 1.37kg while the red iron oxide peaked at 0.86kg. Burn duration was similar. https://www.youtube.com/watch?v=zn0WFVRB5UI I plan on performing more tests by increasing the spindle length on each fuel. I feel like using copper oxychloride will make a more powerful rocket with longer spindles, but I wonder if there is a point where a red iron oxide whistle can use a longer spindle without a CATO resulting in higher available thrust.
leedrill Posted May 13, 2014 Posted May 13, 2014 hey nater glad to see some one playing with some whistle motors again may i ask is the tooling perhaps the same set i have i got mine off cali so youd have to ask him but i digress i have some copper oxy and the whistle i made with it was a fair bit faster in all circumstances but made more of a difference with the benzoates then na sali didnt seem to gain too much from the copper oxy just sounded different my question to you is if you have the same spindle as me and a test stand can you make a motor like mine and test it too see what power im actually making just wondering if youd be keen in doing it too see your self
nater Posted May 13, 2014 Author Posted May 13, 2014 The tooling I made those whistles on is tooling for 1" motors with interchangeable 1/4" stainless steel taper pins as the spindle. Those used a 1" long spindle. I also have Universal tooling in 1/2", 3/4" and 1", a 1/4" SBR set and a 3/4" stinger tooling which all work with whistle. If any of those look like they are close to the tooling you have, I would be glad to press and test a motor for you. The results should be close, but chemical quality, mesh size, loading pressure and the technique to make the fuel all effect the power. Our next shoot is in June, and that is when I will test more. I am already planning on more ground testimg with different lengths spindles with my 1" taper pin set.
leedrill Posted May 14, 2014 Posted May 14, 2014 Ok so I wish this was like face book and I could just tag Cali but I'll ask him him where he got the 3lb set but mine sounds a lot like the set you have is a base with interchangeable spindle base and spindle I have a 3" 4" and 5" what would appear to be stainless spindles I use to only use na Sali but my process now is I coffee mill the k Benz ( k Benz also from Cali ) I have very fine Chinese perc that I use at the moment I currently use 70 pecr / 30k Benz / 1red iron ox / 3 Vaseline I screen everything about 6 or 7 time through I'd say a 100mesh screen maybe 80 Then have the vasoline and acetone in hot water ready dump it in knead it screen it to about 20mesh And press The motors I'm currently making are with that mix that method 7.5" x1" Id nept tubes and the 5" spindle they lift quite a lot Hope to here back from you on your thought on this
nater Posted May 14, 2014 Author Posted May 14, 2014 Here is a picture of my 1" tooling and some of the different taper pins as spindles. The 5" taper pin is currently mounted in base, the long rammer is drilled all the way through and the short one is solid. Your method is a little different than mine. I am also under the impression that 70/30 +1 whistle is a little slower burning than 76/23/1. I do have plenty of K Benz, I'll make up some whistle in that proportion and see what happens. I don't think I will be able to burn them until our next shoot though. 1" whistles are a little loud.
leedrill Posted May 15, 2014 Posted May 15, 2014 Haha no they arnt very back yard friendly haha And would be ever greatful to see some results Ps. My tolling is exactly the same as yours but I have a longer rammer or I use my wolter coreburner rammers because the longest rammer dosnt allow me to use 7.5 " tubes
nater Posted May 15, 2014 Author Posted May 15, 2014 I see, that will make comparing some notes a little easier. Do you get good compaction around the base of the spindle on your first increment with the oversized rammer? These taper pins are quite a bit more narrow than the other tooling sets I have.
leedrill Posted May 16, 2014 Posted May 16, 2014 I will say that the compaction is not as good as with a rammer suited to the spindles but it makes a solid grain and have never had any problems with fuel being pushed between the spindle and rammer if anything I get less of that than with the suited rammer I don't know I you have watche any of my whistle motors nater but the lift 500 g of shell effortlessly to quite a height and I run too much delay I'd be really keen to know what a 5" spindle can lift with my fuel but I'd assume a lot more than 500g seeing as my bp coreburner will lift 1kg
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