dagabu Posted January 24, 2015 Posted January 24, 2015 One question, why do you want to use these verry skinny spindles.What is the advantage of such a skinny spindle compared to a fat one like on bens nozzleless rocket set? The skinny spindle lets you press more fuel in there for a little longer burn time. With Maserface's tests last week, the burn time (whistle) was actually shorter with the skinny spindle and the impulse was almost 20% greater with the skinny spindle v.s. a "standard" Fatty Mc Fatster spindle. This is a trend once again, I think you will see a lot of skinny spindles this next year. For me, it is the promise of being able to use spiral would tubes with hot propellants since the chamber pressures are mostly held by the grain itself rather than the tube walls when the burn starts. Once the grain is thin enough the the tubes is needed to contain the grain, the speed at which the motor is flying by that time helps greatly reduce the nozzle to atmosphere pressure differential and helps keep the motor intact. It is exciting to see this addition become common place to the rocket community.
calebkessinger Posted January 24, 2015 Posted January 24, 2015 (edited) I'm with Dagabu on this one!!! my bet is all in on the skinnies!!! He's been spinning some andI know I am making them as fast as the lathe will allow!!!!! Yes Some people we know have been using them for years without really making it known. But the word is out now. Get yours on the way so you can keep up with the jones's !!!! Edited January 24, 2015 by calebkessinger
FlaMtnBkr Posted January 24, 2015 Posted January 24, 2015 I have made nozzle less BP rockets with as hot of BP as I can for around 14 years now. I started with home made tooling that uses a nail or wire as the core. I have since bought some tooling but still like my home made stuff, especially in smaller sizes. From my seat of the pants feel they seem more powerful. Have no way to test power and they all go so high I lose sight of them usually and have no idea about height. I figured the extra BP was helping. I tried to tell people 14 years ago but was told they wouldn't work without a nozzle.
dagabu Posted January 24, 2015 Posted January 24, 2015 I am in the shop all day spinning skinny spindle sets for 4" long 0.75" tubes (spiral wound) that will come with 150 FREE tubes! You will see them in Caleb's store next week.
Maserface Posted January 24, 2015 Posted January 24, 2015 It's going to require a lot more data before I'm convinced, but it's looking good. Unfortunately everyone who had used skinny spindles before never spoke up, and there aren't many test rigs in the hands of those willing to experiment. Dave F is getting some to test, he hopefully will get some answers about bp, as well as hopefully quantify my results with whistle. I'm glad this idea is catching insterest. I'm mobile now but I'll start a thread here with y results when I get a bit of time.
ddewees Posted January 24, 2015 Posted January 24, 2015 (edited) Good luck with the spiral tubes. With more fuel, you'll get even more expansion after the support is released. I predict more split tubes than anything. I wish you the best though Dag. For me, I've thrown way too many rockets in the burn pile to ever use a crappy spiral tube again. BP seems to work though, but I'm not stocking different tubes just to save a buck. I also don't think skinny spindles are a wise investment. They're for guys who like to shoot rockets upside down attached to a computer. Hell, I've got a 3lb spindle with a 0.165 inch core (that's skinny). Can I get it to fly? Sure... but not as consistently as a standard set. Don't get me wrong though, I love a salute on a stick as much as the next guy, but enjoy the flight even more. Edited January 24, 2015 by ddewees
dagabu Posted January 25, 2015 Posted January 25, 2015 Good luck with the spiral tubes. With more fuel, you'll get even more expansion after the support is released. I predict more split tubes than anything. I wish you the best though Dag. For me, I've thrown way too many rockets in the burn pile to ever use a crappy spiral tube again. BP seems to work though, but I'm not stocking different tubes just to save a buck. I also don't think skinny spindles are a wise investment. They're for guys who like to shoot rockets upside down attached to a computer. Hell, I've got a 3lb spindle with a 0.165 inch core (that's skinny). Can I get it to fly? Sure... but not as consistently as a standard set. Don't get me wrong though, I love a salute on a stick as much as the next guy, but enjoy the flight even more. Absolutely! These are free tubes that go with a tooling set so there is no problem with the tubes being spiral. I do disagree with your hypothesis about expansion though, with a support and hand ramming or low pressure pressing with no dwell time, I got 20 of 20 to fly (BP only mind you) last fall in November. Not a CATO in the bunch. A very good beginner rocket.
ddewees Posted January 25, 2015 Posted January 25, 2015 For me, it is the promise of being able to use spiral would tubes with hot propellantsI was referring to this comment.
dagabu Posted January 25, 2015 Posted January 25, 2015 I was referring to this comment. Gotcha! My mind (which seldom do my hands catch up with) was refering to the ones Phil sells, mine are thin walled tubes, not suitable for energetic propellants, sorry for the confusion.
ddewees Posted January 25, 2015 Posted January 25, 2015 I was referring to Phil's also... they're not suitable for whistle. Many others have contacted me with the same results I had, but haven't posted that info. Try them, you'll hate em.
nater Posted January 25, 2015 Posted January 25, 2015 Funny. I have had good luck so far with Phil's tubes amd whistle. I had some issues with them and BP.
Col Posted January 25, 2015 Posted January 25, 2015 I found spiral tubes tended to compress downwards even before removing the support, i couldnt use more than about 2100psi with a 3/4" without damaging the tube one way or another. It would be interesting to make the tube from a slower burning comp pressed at high pressure. Keeping the stick attached could be an issue. On the plus side, only the stick comes back down..hopefully not ablaze
oldspark Posted January 27, 2015 Posted January 27, 2015 (edited) I just pressed a whistle rocket on Phil's sprial tubes tonight at 4500 loading pressure (no tube support) and it showed no signs of failure. Edited January 27, 2015 by oldspark
ddewees Posted January 27, 2015 Posted January 27, 2015 Go light it, get video too. It don't count unless it flies... just sayin.
oldspark Posted January 27, 2015 Posted January 27, 2015 Go light it, get video too. It don't count unless it flies... just sayin.When I said no signs of failure that ment it flew perfect, I have a limited plan for internet so dont do videos for the most part.Not sure why your tubes did not work, what was the problem?Are you waxing the tubes?
wildcherryxoxo Posted January 27, 2015 Posted January 27, 2015 What do Phils tubes, and WHISTLE rocket tooling tests have to do with the topic of this thread, nozzle-less BP rockets? I dont get the impression that Maserface's tests with skinny spindles were to include BP rockets.
calebkessinger Posted January 27, 2015 Posted January 27, 2015 (edited) OH ^#$^%# Thread police....sorry too harsh.. Threads are just conversations that sway with people's thought...Do you get pissed when someone changes the subject while standing in front of you? Just saying , If you want people to be respectable of your opinions try not yelling at them every time they change the subject.. Edited January 27, 2015 by calebkessinger
calebkessinger Posted January 27, 2015 Posted January 27, 2015 Great news on phils tubes oldspark!!!!! congrats!!
Mumbles Posted January 27, 2015 Posted January 27, 2015 OH ^#$^%# Thread police....sorry too harsh.. Threads are just conversations that sway with people's thought...Do you get pissed when someone changes the subject while standing in front of you? Just saying , If you want people to be respectable of your opinions try not yelling at them every time they change the subject.. Caleb, this isn't Fireworking. We actually do try to make a general effort to keep things on topic around here. To me, forums can be as much of an information repository as a place to converse and talk about pyrotechnics. Threads where the topic wanders wildly make it very difficult to find information later on when searching. Certainly all conversations have a certain flow to them, but at some point things occasionally need to be re-focused.
dagabu Posted January 27, 2015 Posted January 27, 2015 (edited) Forgive the opinion but whistle rockets are nozzleless too aren't they? The topic is "Nozzle less Rockets" so I believe it still pertains even if spiral wound tubes and whistle are added to the conversation. I think if there is a disagreement to this chain of thought, it should have been addressed when I admittedly resurrected a five year old thread. I will be happy to move this to a new or other thread that more closely follows the originators intent but I frankly don't see a great departure. Edited January 27, 2015 by dagabu
Mumbles Posted January 27, 2015 Posted January 27, 2015 Also true. I wasn't actually taking any offense to this thread or the topics being discussed therein. Just a general mild frustration of mine as of late.
dagabu Posted January 27, 2015 Posted January 27, 2015 Also true. I wasn't actually taking any offense to this thread or the topics being discussed therein. Just a general mild frustration of mine as of late. Gotcha! Yes, I know that I wander a lot and really did try to open and old thread instead of polluting the forum with yet another thread. Again, I am happy to move it to a new thread if you wish.
ddewees Posted January 27, 2015 Posted January 27, 2015 When I said no signs of failure that ment it flew perfect, I have a limited plan for internet so dont do videos for the most part.Not sure why your tubes did not work, what was the problem?Are you waxing the tubes?Since it's OK, I'll reply... I didn't wax any of the tubes. Until they come that way, I'm sticking with unwaxed. The tubes I was talking about are the 1 inch diameter (3lb) tubes. If you press whistle motors to 8000-9000 psi, they split once you remove the support.
calebkessinger Posted January 27, 2015 Posted January 27, 2015 (edited) I apologize.. I do understand mumbles. Thanks for setting me straight. I will not wander or lend to it. It's not really bad to know what's expected from you. Now I know. Edited January 27, 2015 by calebkessinger
oldspark Posted January 28, 2015 Posted January 28, 2015 Since it's OK, I'll reply... I didn't wax any of the tubes. Until they come that way, I'm sticking with unwaxed. The tubes I was talking about are the 1 inch diameter (3lb) tubes. If you press whistle motors to 8000-9000 psi, they split once you remove the support.Oh mine were 3/4 and pressed at 4500 with no support, I really think the waxing helps and its very easy to do.Not sure what I can post over here.
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