usapyro Posted October 21, 2012 Posted October 21, 2012 How do you separate your stages in a rocket when it's in flight? I have used technique 1 a lot... Just tape the two stages together with an extra stronger wrap of tape on the lower stage and let them blow apart. It can be a little more erratic than one would want... I am moving to technique 2 now. Wrapping the stages and creating a paper tube which is then taped to the lower stage. This should align the upper stage perfectly straight with the lower stage. I have thoughts about another 3rd technique... Simply aligning and gluing the stages together with a nitrocellulose lacquer composition. Does anyone have any thoughts on this? Is NC strong enough to bind to cardboard/paper? Maybe a different type of flammable epoxy/glue composition can be used. http://i50.tinypic.com/348mvf7.png
usapyro Posted October 21, 2012 Author Posted October 21, 2012 (edited) Another thing that might help with stable non-erratic separation is using a proper delay increment to reduce rocket pressure. The orange is fast fuse.http://i47.tinypic.com/33cal2w.png Possibly also helpful with technique two would be to drill two pressure release holes in the middle of the delay increment to insure the rocket doesn't separate from the previous stages pressure created by the delay increment before the next stage fires. Probably could just drill straight through the entire rocket. That will insure that each nozzle releases pressure in perfectly opposite directions and won't effect the rockets trajectory. Either that or I could find a good medium speed burning delay composition that produces very little gas? http://i45.tinypic.com/sqgztd.png Edited October 21, 2012 by usapyro
TheArchitect23 Posted October 21, 2012 Posted October 21, 2012 well id figure you could do something like this: Any dual stage i have seen seemed to have a separation "blast" of some sort.
usapyro Posted October 21, 2012 Author Posted October 21, 2012 LoL... I don't think anyone could manage that design without changing the trajectory of the rocket around 15-30 degrees each stage separation...
usapyro Posted October 21, 2012 Author Posted October 21, 2012 I have decided this is the design I am going to test with my next double stage... Technique 2 + Delay Increment Added + Clay Bulkhead with SMALL hole + Very small sticky match tube. http://i50.tinypic.com/164gah.png
Short5 Posted October 21, 2012 Posted October 21, 2012 (edited) In model rocketry a paper sleeve is used as a coupler and/or a piece of Scotch tape is wrapped around the point where the engines meet. The Estes model engines used as a booster stage have no clay bulkhead or delay and the flame from the booster ignites the next stage as well as burns through the thin plastic tape instantly. No fuse or powder charge is used to transfer the flame to the next stage. Edited October 21, 2012 by Short5
dagabu Posted October 21, 2012 Posted October 21, 2012 (edited) I was able to get some advice from some of the old snorts over the years at PGI and online about two and three stage rockets and there is a wide variety of methods to use but it seems that there is a single constant that I got from them all. Remember that the ESTES motors are held in place with rings, the tape keeps the bottom one from falling out and keeping a tight seal but does little to ensure alignment under stress. Make a paper coupler at least X4 the OD of the motor so that each end of the coupler is X2 the OD long. This keeps each motor rigid and aligned which is the most critical part of multistage rockets, any deviation will cost you LOTS of thrust. Glue the coupler to the BOTTOM motor only, the upper portion of the coupler should friction fit and not be sloppy. Using a charge is up to you but I have found a charge to be unnecessary and can break the nozzle of the top rocket. -dag Edited October 21, 2012 by dagabu
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