Introduce myself

Discussion in 'Gallery & Designs' started by NOBI, Feb 5, 2004.

  1. NOBI

    NOBI Active Member

    Hi All,

    I think many many modelers who build many many papermodels will have a dream, that dream is about have own papermodel with own design :D This section will make your dream come true, This is a section to make change of some modeler, This is a section of modeler who want to be a designer.

    I'm NOBI. I'm glad to be here as moderator of this section. I must said that I'm not an expert on designing model. :oops: I design papermodel because I love to design. I want to share my technics or try to answer all question about design papermodel.

    Welcome all modeler who want to be a designer or every designer to this section, you can share your technics, share your model, share your happily here. I will do the best as I can do...

    Thank you very much, Ron to give me a chance... :wink:
  2. kooklik

    kooklik Member

    Hi Nobi
    I'm starting to design a u-boat with Rhino. I have a problem with unfold feature. Some hull plate I can't unfold it cause curvature analysis show me some red and blue area on the plates. How can i solve it ?

    ---- K ----
  3. marian

    marian New Member

    You need to make sure your hull segment is developable.

    Rhino does determine this with near-mathematical accuracy, whereas paper in fact _can_ be formed spherically to a certain degree. So the fact that Rhino does not unroll a surface does not imply that you cannot in fact build the part.

    My solution is to make Rhino happy in the 3D world and fudge the things I still need to fudge when moving to 2D.

    How did you arrive at the surface that cannot be developed? Can you show the part? Or make it available for download[1]? I am sure lots of people are willing to help you with it. I for one would as I have received similar help myself.

    Ciao, MM

    [1] Do a "save as" under a different name, remove everything that is not required to debug the problem. Keep adjacent parts.
  4. kooklik

    kooklik Member

    Hi Marian
    Thanks for your help

    Here is my Rhino file. All hull plates I can unfold them except the red one. Could you please suggest why Rhino told me "Unable to unroll that object"?
  5. kooklik

    kooklik Member

    Sorry I missed attaching the file.

    Here is the attached file.

    Attached Files:

  6. wunwinglow

    wunwinglow Active Member

    ..because the bottom edge of the red plate is a curve. Draw in a new line (called a curve!) and then use the 2 rail sweep command, with the forward edge of the red plate, the forward edge of the white plate immediately aft as the two rails, and the STRAIGHT curves top and bottom (ie the original straight top edge, and the new straight line you just added) as the cross section curves. The new plate will then unroll properly.

    To unroll successfully, a surface can only be curved in one direction. In this case, the front and back edges were curved, but the top and bottom edges were straight lines. Your original plate had a curved bottom edge, so the whole surface was curved in TWO directions; that is why it would not unroll.
    Hope this helps!

    Tim P (wunwinglow)
  7. marian

    marian New Member

    The problem is the bend in the keel in the area of that plate. You have at least two options I can think of right now (not a Rhino-expert myself):

    1) Add a straight section of keel between the formers.

    I did that in the attached version on Layer "new plate 1". Then sweep2 that section of keel along the front and aft former cross-section and the straight connection at the top.

    This modifies the lines of the hull when viewed from the side.

    2) Make two plates.

    To do that you need another cross-section at the station of the bend in the keel. I arrived at one by first creating a vertical plane through that bend, intersecting that with the plate I had made and then scaling that cross-section down to the bend in the keel.

    Then you have two parts of the hull with curved sides and straight tops and bottoms. You can Sweep2 them separately.

    You may find when unrolling and checking out into the 2D world, that the difference between the unrolled edges is "small enough" to allow them to be built in one piece. You can then merge the two parts in 2D. That is the "fudging" I referred to.

    Hope to help, MM

    Attached Files:

  8. kooklik

    kooklik Member

    Hi guys
    Very thanks for helping me. I can continue unrolling right now. Finally i straitened the keel and re-devided crossection lines to match with the keels corners. It goes easier. :)

Share This Page