usapyro Posted January 7, 2012 Posted January 7, 2012 (edited) A sugar rocket end burner that burns fast enough to lift payloads... Wouldn't that be the ultimate in a easy high power rocket!?! Think of how much more power that fuel has than BP... Too bad it doesn't burn fast enough even with the proper burn catalysts! If you try to slim the nozzle way down for increase pressure then you run into the issue that a plain bentonite nozzle won't work for those pressures and oh my god you just run into headache after headache... The rockets are too touchy, Cato galore... Etc!!! Now, I have just though up a SOLUTION which is easy to construct and should be reliable!!! Excuse me if I am a bit rocket obsessed lately... Cast grain first, ram bp core/end. and then form nozzle. It's built in the reverse of normal. Now don't shout "cracked grain when ramming core!!!" I am going to use a semi flexible high syrup(Karo Light) fuel. This should work! Using a cooked then powdered sugar fuel may be easier. http://i43.tinypic.com/ekqkj6.gif Edit: Yes... I do realize this thing is going to launch fast... Slow down, make everyone nervous, and then steadily pick up speed again as the flame front forms up on the sugar grain. Haha Probably should put a half inch core into the BP to maximize the effect. Will be funny. Edited January 7, 2012 by usapyro
usapyro Posted January 7, 2012 Author Posted January 7, 2012 (edited) Just in case you didn't get what I was talking about when it comes to the launch, pause, then acceleration effect... A picture is worth a thousand words. I'm thinking a slightly slower mineral oil BP or whistle will be best. It also will insure the core grain is more moisture resistant and reduce flame front slope a little while still giving good speed. One of these without the initial boost BP grain would make for a space shuttle slow takeoff... Yet steadily accelerate to massive speed!!! Maybe a touch of FeTi too if it won't melt. Hmmm...http://i42.tinypic.com/27ymlac.gifWoah... I think I just realized how those super cool looking super slow takeoff rocket engines that slowly accelerate to insane speed are made... This must be it! A slower grain surrounding a faster core!!! Omit the BP booster. Woot... Too excited to try these... Can't sleep!!! You should be able to get the slow launch effect with any combination of significantly slower and faster fuels and the proper nozzle size. Edit: Added stable thrust curve version below for those who wouldn't care for the zoom>pause>acceleration effect. I wouldn't bother with this personally. Too much hassle shaping the sugar grain. A easier solution that would somewhat help is to just put super-hot bp or whistle a inch into the sugar grain on the original design.http://i42.tinypic.com/35j9n5f.gif Edited January 7, 2012 by usapyro
dan999ification Posted January 7, 2012 Posted January 7, 2012 very nice idea, and part of the reason i give em up..... too touchy, i thought of a similar one for cored bp rockets where the core is either normal green bp, 60/30/10 or another non optimised fuel/ratio, the walls of the tube are lined with fast bp or super bp or whistle obviously made in reverse, slow take off with no cato and when the grain burns away the hotter fuel kicks in and makes up for the loss in thrust due to the extra volume.making such a thing is beyond me at the moment, but i love to daydream pyro dan.
usapyro Posted January 7, 2012 Author Posted January 7, 2012 (edited) Ill make one tomorrow and tell you how it goes. I don't like being constrained by tooling. I am always experimenting and I have gotten quite skilled with drill bits, molded hot glue(I make molds and fill them with hot glue to make custom shapes which can also be attached to a dowel.), and wooden dowels of a zillion sizes. The tools don't last long, but I usually get bored of a design before they wear out. There is a old wood lathe in the family shop but I suck with it... I blame the old dull bits!!! Btw, does anyone have any suggestions on making cooked then powdered sugar fuel? What I have done before is just cook KNO3/Su/iron Oxide sugar fuel like normal with water, boil off the water, and then make it into small chunks which are then cooled. Those are then added to a blender a small amount at a time and blended into powder. It makes a LOT of noise... But, you end up with a nice fast burning granulated fuel that is easy to compact. Edited January 7, 2012 by usapyro
dagabu Posted January 7, 2012 Posted January 7, 2012 Btw, does anyone have any suggestions on making cooked then powdered sugar fuel? First: Fantastic designs, I am envious of how you think I like the potential of the composite fuel grains and agree that a granular sugar fuel would be much easier to work with. I only use granulated sugar fuel in sugar rockets, I really hate making Bates grains and pushing semi-molten goo into tubes so after talking to Lloyd and Jimmy on another forum, I started to granulate and press sugar rockets. They work very well, are easily pressed onto modern tooling (you do need a release) and leave copious amounts of white smoke for daytime rockets. Here is how I do it. Electric skillet (a MUST) to 350° F, add sugar, KNO3 and water, heat until the first color change to straw, add corn syrup, keep stirring! Everyone seems to have a different place and heat for the final step, I turn the temp down to 280° F as soon as I get a crumbly appearance and continue to cook until I get the color I want (Brach's caramels in cellophane) than unplug the pan. Take the mix and bring in to the kitchen (the only time I have pyro in the house), form balls of the fuel in my hands (leather insulated with a tiny bit of pan spray on the palms) and grate the fuel using a cheese grater onto waxed paper. Let cool, IMMEDIATELY bag it up with a desiccant bag and store. If kept in a freezer, one can use a rolling pin to crush the fuel to even finer pieces or yous bring to room temp and press as you would with BP. -dag
allrocketspsl Posted January 7, 2012 Posted January 7, 2012 powdered sugar kclo4 iron oxide granulate then press add feti for tail if wanted core like bp rocket kick butt fuel press only
usapyro Posted January 7, 2012 Author Posted January 7, 2012 (edited) Nice fuel allrocketspsl, got any ratio's for us? Edited January 7, 2012 by usapyro
allrocketspsl Posted January 7, 2012 Posted January 7, 2012 Nice fuel allrocketspsl, got any ratio's for us? 70/30/02 if adding metal no more than 2 percent i use to make 3/4 ID by 7.5 long same as one pounders!Small ones I can say how to do!
usapyro Posted January 8, 2012 Author Posted January 8, 2012 (edited) Just launched a 1-1/4" ID one... LoL!!! As sugar fuel I simply used 65/35 KNO3/Su ground extremely fine and 1% iron oxide added. I omitted the initial BP grain and just launched it from a tube. What a roar... I was kind of mystified by the fact I could still see the engine flame halfway through the rockets flight, yet I couldn't hear it anymore... I was like "Huh, I can see the engine flame yet I can't hear anything anymore... Whats going on here?!?" Not sure how high it went as it had a perfectly straight up flight and I was only standing twenty five feet away. Could barely hear the 2g salute heading on the thing. This design is confirmed to work just awesome!!! Final simplest and easiest version... It maintains a stable burn rate from launch until the end of the BP grain is reached. End burner and end burner hybrid rockets like this are the ONLY type that can get you perfectly stable burn rates for a long duration.http://i39.tinypic.com/2iudopw.gif Edited January 8, 2012 by usapyro
usapyro Posted January 8, 2012 Author Posted January 8, 2012 (edited) I have a few witnesses. I don't think that works legally because I am related to them... It's such a simple rocket. If you can make a sugar core burner you can make one of these. The only difference is a slightly smaller nozzle and BP rammed inside the core. I need to get some new videos up, but all I do lately are night launches... Ugh, it's such a pain in the neck to hand ram a 7.5" x 1-1/4" ID sugar rocket... BP compacts so much easier. I can't go any longer because drill bits are only so long! Edited January 8, 2012 by usapyro
californiapyro Posted January 11, 2012 Posted January 11, 2012 i feel your pain... ive tried my hand at drilled wooden tooling and can't get a sufficient core because my drill bits don't go that far
dagabu Posted January 11, 2012 Posted January 11, 2012 Look for Aircraft Drill Bits online for longer then normal bits and "extra long drill bits" for the really long ones. The $ you spend is well worth it, just select a few of the most used sizes and you will be all set. I have them in 1/8", 1/4", 3/8" and 1/2". They are essential for boring cores in tooling. -dag
Col Posted January 11, 2012 Posted January 11, 2012 Grab some video footage of the next flight so you can use the delay between the flash and the bang to calculate the height.
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