Colt T Posted July 11, 2006 Posted July 11, 2006 this is my first post, so please bare with me. ive been doing tons of combustion related projects. hybrid spudguns, firearms, incindiearies and very elementary fireworks/rockets. but i would like to take it to the next level and start rocketry, with out using a "kit"i was thinking: aluminum tube for the body, fiberglass nose and fins. would this be safe? should i start with cardboard? as for fuel, im lost. the kno3/sugar fuel seems promising, and its probably what im going to use but it seems hard to obtain. i am also interested in an ammonium ntrate fuel, because i can get it out of $0.80 cold packs. i am kind of scared of it though . and dont worry, i am taking it slow, and NO chances thanks Colt T.
Bug_X Posted July 11, 2006 Posted July 11, 2006 this is my first post, so please bare with me. ive been doing tons of combustion related projects. hybrid spudguns, firearms, incindiearies and very elementary fireworks/rockets. but i would like to take it to the next level and start rocketry, with out using a "kit"i was thinking: aluminum tube for the body, fiberglass nose and fins. would this be safe? should i start with cardboard? as for fuel, im lost. the kno3/sugar fuel seems promising, and its probably what im going to use but it seems hard to obtain. i am also interested in an ammonium ntrate fuel, because i can get it out of $0.80 cold packs. i am kind of scared of it though . and dont worry, i am taking it slow, and NO chances thanks Colt T. Welcome. This websits are VERY good http://www.nakka-rocketry.net/http://www.jamesyawn.com/ And I think you should have post this in one of the rocket threds. (my English suck) / bug
Ozzy Posted July 12, 2006 Posted July 12, 2006 You have better chance of your pillow blowing than the NH4NO3 unless its mixed with a sensitiser
DeAdFX Posted July 17, 2006 Posted July 17, 2006 Ammonium Nitrate will only burn reliably with Magnesium powder. Ammonium Nitrate will sort of work with charcoal and works ok with cellulose. I have tried using other combustable material like polyurethane, sugar, aluminum and countless and these do not work. The stuff is pretty stuborn at liberating its oxygen.
Exerd Posted July 19, 2006 Posted July 19, 2006 Greetings, When you say you are not looking for a "kit", I assume you are talking about getting into experimental rocketry, and not single-use pyrotechnic rockets. Is this correct? What are your actual goals from your rocket design? Simplicity, performance, low-cost? Just how big are you planning on going? This can be a tricky road to perfection, and is best if absorbed slowly, and started out small. If you are looking for all out performance, and lots of possible flame colors, I recommend you first try designing motors using ammonium perchlorate and ground testing them. They are extremely simple to produce, and yield some of the highest impulses per weight available. You will probably find that you will lose/destroy more rockets by using a delay grain to set off your ejection charge, so for the amateur I typically recommend an electronic means of ejection, I swear by this. This way, you can use your delay for a smoke grain and have no worries about correct timing to deploy a chute. Overall, I would say by no means that rocketry is a cheap area to experiment with. However, it definitely has its rewards. Once you have got the motor making part of it down, then you will want to start trying to design your airframe. In amateur rocketry, there is no rules against your airframe design. Therefore, use what suits your needs the best. Some may find it suitable to use aluminum, while others may find it more cost-effective to stick to phenolic/cardboard/fiberglass airframes. I personally produce carbon fiber airframes when all-out (lightweight) performance is required, but I also currently have a boosted-dart setup to break 100,000 feet, which uses 100% machined aluminum for the components. This is basically needed to prevent the dart from melting at mach 4+. Stresses will be your prime factor in developing an airframe/fin design. But again, I recommend you start very small and work your way into the more advanced designs. This way, you will know your design will work/fail under the flight physics, rather than wondering if it will. And even then, you will have your share of airframe failures. If you are also wondering where all these various components are available from, just ask. Hope this helps.
PyroMan16 Posted August 17, 2009 Posted August 17, 2009 When I built my first rocket I just use good cardboard, glue, and basswood for the fins. It worked perfectly for a long time and was super cheap and easy. My advice would be to start out with cardboard and as for fuel you should start with a sugar based fuel, composite fuels require lots of experience to make and would probally rip the fins off a cardboard rocket.
Exerd Posted August 18, 2009 Posted August 18, 2009 Over 3 years after my post, someone replies to it. I'm glad someone out there had enough time to respond, even if it took a while. composite fuels require lots of experience to make and would probally rip the fins off a cardboard rocket. Rip the fins off a rocket? That is the entire goal us AP propellant guys are trying to achieve. In all honesty, composite fuels are not hard at all. You buy the materials, mix them up in a kitchen mixer, add curative towards the end, and begin packing rolled balls of propellant into your cardboard casting tube. You can use a coring rod, but when it is pulled out (when propellant is about halfway cured), it can sometimes leave imperfections and increased surface area down the core just from the propellant still being soft. Wait too long, and the rod wont come out. I now prefer to cut all grains to length after packed and cured, and drill the cores out at a very low speed on a drill press. Then the cores are perfect cylinders. What you then do is shine a bright LED flashlight down the core. It should look perfectly smooth all the way down. If you see air pockets in the cylinder, your motor is probably going to explode. This is why large batches of propellant are vacuum degassed before curing. AP propellant RIPS. If you want to see something leave a hole in the ground from thrust, and leave like a bat out of hell, I recommend you attempt it.
PyroMan16 Posted August 18, 2009 Posted August 18, 2009 Ha thats a good goal and yes composite propellents probally aern't that hard to make but since its his first ¨real¨ rocket i woulds use a less powerful fuel and then gradually move up till he builds a metal rocket and uses composite fuels. Baby steps
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