SpakFace Posted March 22, 2006 Posted March 22, 2006 Thanks for the replies, I will actually test a whole bunch of fillers and sealants from my local hardware store. Fireproof cement and silicone look promising and I'll post my results later.
Caleb51 Posted March 25, 2006 Posted March 25, 2006 I know very little of rocketry. Do you mix the powders and stuff em in a tube, or like melt them together or something?
[w00t] Posted April 19, 2006 Posted April 19, 2006 I was bored so i made this http://img82.imageshack.us/img82/5619/thickrocketmotor6js.th.jpg Consists of Kno3/Sugar/fe2o3 (used dextrin and water instead of melting it) Should i use a stick to get it flying or something else? I usually make small 1/2inch ones where i use a bambo stick.
Draco_Aster Posted April 19, 2006 Posted April 19, 2006 How did you dry it? Wouldn't it cruble/crack/shrink in the oven?Its very short and fat....it looks like you could make a few more stages for a larger rocket but you will need a longer engine to put it on a stick because it wont be able to burn enough propellant at a time to get enough thrust. Correct me someone if I am wrong.... Oh yah....nice looking fingers
[w00t] Posted April 19, 2006 Posted April 19, 2006 Er i made thick and shorter ones that flew well over 50 metres. I haven't dried it yet, usually mine cracks after its fully dried which makes me think that dextrin is total crap. Whats this comment about my fingers, the black under my nail is a bruise, anyway my hand healed ages ago, just gotta wait till the top skin on my middle and index finger gets reformed over.
rocket Posted April 19, 2006 Posted April 19, 2006 So what you’re saying is that its a nozzle less rocket or is it an insert?
[w00t] Posted April 19, 2006 Posted April 19, 2006 None of the rockets i make have nozzles. I find no real differents with or without. I'd be making the case longer.
Caleb51 Posted April 19, 2006 Posted April 19, 2006 Okay, how do you guys get the MELTED kno3/sugar mix into tubes? I have an amzingly hard time doing it. So if I make my mix (Melted), put it in a tube, stick a stick in it for a core, put it on a stick (The right length of course) put a fuse in the core, and light it, will if fly?
[w00t] Posted April 19, 2006 Posted April 19, 2006 Yes it would fly. Thats what i do. It's easy to put the melted mixture in to a tube, mine takes around a minute to set. While its melted and hot, use a spoon and scoop it and then let it drop in to the tube, it usually sticks to the spoon so use another spoon to help it drop in to the tube by scraping the shit off the other spoon.. If that makes sence.
Zeppelin Posted April 20, 2006 Posted April 20, 2006 Yours takes a minute to set? Mine lasts no more than mayby 20 seconds... How long\at what heat do you cook yours at?
Zeppelin Posted April 20, 2006 Posted April 20, 2006 I was just reading through what was said earlier in this thread, about the nozzles, I just use damp corn starch to fill the ends, then it dries and i drill the hole, let the engine sit in a ziplock with salt for a day or so (to dry it out i guess) and this seems to work well for me.
rocket Posted April 20, 2006 Posted April 20, 2006 I just use cat litter (free out the packet clean) and just ram it in the end of the tube works well I think I got to use more next time it blows out half way in flight or I might just make the nozzle hole bigger to cope with the pressure.
FrankRizzo Posted April 20, 2006 Posted April 20, 2006 I just use cat litter (free out the packet clean) and just ram it in the end of the tube works well I think I got to use more next time it blows out half way in flight or I might just make the nozzle hole bigger to cope with the pressure.The cheapest grade of kitty litter is great stuff for rocket nozzles. I use Home Best brand or Wal-Mart’s "Special Kitty." You need to ram your nozzles to the point that the casing expands slightly, locking the nozzle in place. Adding a bit of quartz sand or grog to your kitty litter will help if you're already ramming as hard as possible. If you have erosion issues, that's also solved by increased consolidation force.
[w00t] Posted April 20, 2006 Posted April 20, 2006 I left my rocket motor outside under the sun. It went all gooy. Weird. i tried to put it in the oven to dry the remanding water at 80*c and it went all soft and gooy aswell. then i took it out of the case and melted the mixture and put it back in to the case. its been 10minutes and its still gooy
Draco_Aster Posted April 20, 2006 Posted April 20, 2006 My basic 65-35 mix doesnt drip at all and is quite thick. When I said about your finger - It looks scarred between your pointer and middle finger Do you know what I mean? Or is that just something stuck there or the camera playing tricks?
rocket Posted April 24, 2006 Posted April 24, 2006 ,Apr 20 2006, 06:46 AM] I left my rocket motor outside under the sun. It went all gooy. Weird. i tried to put it in the oven to dry the remanding water at 80*c and it went all soft and gooy aswell. then i took it out of the case and melted the mixture and put it back in to the case. its been 10minutes and its still gooy I think I know why your Kno3/sugar went gooey, I made some today and I had to much sugar in it I left it on my desk and now it stick and gooey. Did you weigh the Kno3/sugar on scales or just eye ball it?
realfirewurx Posted April 25, 2006 Posted April 25, 2006 I got it to work with dry sugar KNO3 ill post a vid of one soon.
Caleb51 Posted April 27, 2006 Posted April 27, 2006 I know this is off topic, but does anyone know an easy/safe way to make a HIGH power rocket engine? I have done regular model rocketry for YEARS, but recently wanna try my hand at HP rockets. My goal is to get a (Approximately) 13 pound rocket off the ground. Any ideas? And yes, I have searched google for three days, all I can find is regulations on HPR and a few videos of test rockets, et cetera, but no formulas. Any help would be great.
[w00t] Posted April 27, 2006 Posted April 27, 2006 ,Apr 20 2006, 06:46 AM] I left my rocket motor outside under the sun. It went all gooy. Weird. i tried to put it in the oven to dry the remanding water at 80*c and it went all soft and gooy aswell. then i took it out of the case and melted the mixture and put it back in to the case. its been 10minutes and its still gooy I think I know why your Kno3/sugar went gooey, I made some today and I had to much sugar in it I left it on my desk and now it stick and gooey. Did you weigh the Kno3/sugar on scales or just eye ball it? i weigh it using digital scale 65/35 (kno3/su)
BigBang Posted April 27, 2006 Posted April 27, 2006 Caleb, at the moment I would say you don't have the experience to construct your own HPR engine. It is much more sofisticated than the KNO3/SU or black powder rockets that are so commonly made here. Also, some "exotic" materials are needed to make them. The oxidizer, for instance, is usually expensive in USA and hard to get outside of the country. Also the prefered binder can be hard to find. The actual construction of the motor is more complicated as you must cast your grain, make sure all the fittings are "good" and sealed using silicone O-rings. The pressure are sometimes as high as 1000 PSI so case strength becomes a major factor. I would jus say to stay away from these motors at the moment, period.
Mumbles Posted April 27, 2006 Posted April 27, 2006 I know this is off topic, but does anyone know an easy/safe way to make a HIGH power rocket engine? I have done regular model rocketry for YEARS, but recently wanna try my hand at HP rockets. My goal is to get a (Approximately) 13 pound rocket off the ground. Any ideas? And yes, I have searched google for three days, all I can find is regulations on HPR and a few videos of test rockets, et cetera, but no formulas. Any help would be great. Don't lie, I do come here you know. You were just asking me about HPR yesterday, and at that point you had put in 30 minutes of searching. Weird how you can get 3 days worth of searching in 24 hours. The best thing to do would be to find and join some HPR group in the area. They will help you on the way.
Caleb51 Posted April 27, 2006 Posted April 27, 2006 that was actually monday. Today is wednesday, three days later. Sorry, I guess it wasn't a solid like 72 hours, but I did look through around 6 pages of "google" but whatever, I'm not gonna argue. I guess I will back off the HPR for now. But if anyone does have a good link or any formulas/plans just for refrence, that'd be cool.
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