OpenRocket Help

Discussion in 'Plans' started by Bruiser, Oct 26, 2018.

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  1. Oct 26, 2018 #1

    Bruiser

    Bruiser

    Bruiser

    Well-Known Member

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    Last night I started working on a 1/10th scale Nike-Ajax in OpenRocket but I ran into problems with the forward fins of the sustainer. Basically there is a 2.5" nose cone, then a 5" transition, then the 12" body tube and lastly something like a 2" boat tail transition.

    The problem is that the two sets of forward fine are where the 5" transition is and OpenRocket won't give me the option of fins when I have the transition selected.

    I also tried running the motor mount tube all the way to the nose cone thinking maybe I could attach fins to the "inner tube" but I couldn't select the fin option with the inner tube selected.

    Does anyone have any ideas of how to add the fins to the transition?

    I think I am starting to understand why all most of the Nike-Ajax kits I have seen do not bother with the transition and just keep the same body tube diameter all the way to the nose cone.

    By the way, it showed big problems with the cg and cp being flipped flopped... I think I understand why the Estes rocket was a single stage...

    -Bob
     
  2. Oct 26, 2018 #2

    dr wogz

    dr wogz

    dr wogz

    Fly caster

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    taking a guess here, but I believe should work.. sort of..

    select the upper tube, the one on top of the transition. put your fins on this tube, and move them as far back as you need to intersect the transition..

    i did something similar, but the transition was form a large tube to a MMt tube.. and it was years ago!
     
  3. Oct 27, 2018 #3

    K'Tesh

    K'Tesh

    K'Tesh

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  4. Oct 28, 2018 #4

    Bruiser

    Bruiser

    Bruiser

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    That did the trick. I put a short body tube between the nose cone and transition, added the fins and moved them.

    Thank you,
    -Bob
     

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