another open rocket question

Discussion in 'Rocketry Electronics and Software' started by bobby_hamill, May 7, 2016.

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  1. May 7, 2016 #1

    bobby_hamill

    bobby_hamill

    bobby_hamill

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    when I inserted the fin decals for my rocket it inserted the same pattern on both sides of the fin .
    Is there a way to only insert the decal to 1 side of each fin ?

    on the fin roll pattern for the 4 fin Black Brant 2 one side of the fin is the reverse of the opposite side

    So I need to find a way to put 1 decal pattern only on 1 side of all 4 fins

    Then apply a different decal pattern on the other side of all 4 fins

    See the red arrows in the attached photo for a better understanding

    Thanks !

    Bobby

    fin compare.jpg
     
  2. May 7, 2016 #2

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    Uh... Yes and no.

    You need to duplicate the fins, then offset them ever so slightly, then change your graphic to reflect the design as you want it. When it comes to two items existing in the same place at the same time, OR ignores that. So you'll end up with two unique sets of fins, merged (optically) into one.

    For me, I created a custom material (air) with a mass of zero. My "Air Fins" are labeled for clear identification, and altered to be streamlined. So, the mass stays the same, and it has minimum effect on the altitude. However, OR will change the CP due to that, so it renders the true flight characteristics as suspect.

    Look at one of my decaled .ork files where there are differences on each side of a fin, and you'll see what I'm talking about.

    Oh, and that attachment... That image of the 4 finned Black Brant IIB is just too sexy to leave as a tiny attachment... It needs to be seen...

    [​IMG]

    Ah, that's better.

    Any chance we can talk you into posting your original (no red arrow) image?
     
    Last edited: May 7, 2016
  3. May 7, 2016 #3

    bobby_hamill

    bobby_hamill

    bobby_hamill

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    I have 6 all together
    here is the original one with out the arrows

    dolly.jpg
     
  4. May 7, 2016 #4

    bobby_hamill

    bobby_hamill

    bobby_hamill

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    K'Tesh

    I finally got the fin checker board pattern using the 2 sets of fins method

    Now for the payload section and nosecone

    corrected.jpg
     
  5. May 7, 2016 #5

    bobby_hamill

    bobby_hamill

    bobby_hamill

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    K'Tesh

    the way you set up the image size for the decal wrap

    if the length of the airframe is less than 1 inch would this way be correct ?

    length of airframe is .543 so .543 x 100 = 54.3

    and the diameter is 1.325 x PI = 416

    so the photo image for the decal is

    length = 54.3
    width = 416

    so decal image should be set at 54.3 x 416 correct ?

    thanks !
     
    Last edited: May 8, 2016
  6. May 8, 2016 #6

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    1st... The K goes before the T, not the other way around... K'Tesh (not T'Kesh). Please remember that.

    2nd... You're correct about figuring the length, except you'd need to round the 54.3 length to nearest whole pixel (pixels can't be divided into anything smaller).

    So, the image would be 54 x 416 (or 55 x 416) pixels.
     
  7. May 8, 2016 #7

    K'Tesh

    K'Tesh

    K'Tesh

    OpenRocket Chuck Norris

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    You're correct about figuring the length, except you'd need to round the 54.3 length to nearest whole pixel (pixels can't be divided into anything smaller).

    So, the image would be 54 x 416 (or 55 x 416) pixels.

    [​IMG]
     
    Last edited: May 8, 2016
  8. Jan 6, 2020 #8

    Ez2cDave

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  9. Jan 6, 2020 #9

    Nytrunner

    Nytrunner

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    Be aware, doing this borks the CP position
     
    neil_w likes this.
  10. Jan 7, 2020 #10

    bobby_hamill

    bobby_hamill

    bobby_hamill

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    Nytrunner

    The one with 2 sets of fins is just for looks and decal placement
    I have a second version with only one set of fins for CP

    But good note to point out

    Bobby
     

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