Freeship (3.1.3) Develop plates not showing bottom hull plates.

Discussion in 'Software' started by OldNick, Oct 3, 2019.

  1. OldNick
    Joined: Dec 2009
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    OldNick Junior Member

    Note: I have posted my findings, after much surfing, in a lower post, in the hope that somebody may be helped.

    I have designed a rough and ready single chine double-ended hull, just trying to learn the bases of Freeship. It is not flat bottomed, but has a moderate deadrise.

    I have worked out how to develop the plates, but only the side plates show. The bottom does not. If I check developability, both the side plates and the bottom plate show very mild areas of red. The fact that the sides can be shown developed means to me that the double curvature is not sufficient to stop development of the plates.

    Strangely, when I have mucked about with Hulls32, I get a similar problem, in that if I do the Nesting, only the side sheets will show. (only Chine 1 is available). I would appreciate any help about what I may be doing wrong.

    Thanks in advance.

    Nick
     
    Last edited: Oct 4, 2019
  2. Olav
    Joined: Dec 2003
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    Olav naval architect

    Nick,

    just a thought: Did you tick the box saying "developable" in the layer manager? If not, Freeship/Delftship will ignore the panels on that layer when it comes to plate development. Note: This is completely independent of whether or not the plate is truly developable.
     
  3. OldNick
    Joined: Dec 2009
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    OldNick Junior Member

    Thanks for the reply.

    A GOOD thought! ...But no....;) I have marked the only layer in the design as developable. This is a very simple hull and has default layering (just 1).

    Sorry for the sarky...it _was_ a good thought, seriously. Particularly as that exact thing caught me out at first: I assumed that if the plates were at or nearly developable then the design/layer was developable (within the realms of reality; I believe that FS uses VERY fine tolerances for this).

    What I don't get is that although both topsides and bottom show similar "non-developable" characteristics, one works and the other not.

    The Help seems to indicate that even if I have different parts of a boat in the same layer (like, I assume topsides and bottom) , then developing them will give developments for each plate, but then it hints that placing each part of the boat in different layers will be easier to work with. Correct? Can I take the hull bottom plates/edges/chines and place them in a new layer? Should I need to? It's like the bottom plates do bot exist.

    Thanks again

    Nick
     
  4. OldNick
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    OldNick Junior Member

    OK. I tried again. As "without human input" as possible.

    I started a new design. I asked to have 3 vertical points and everything else vanilla/default.

    I come out with a round chine, with no defined turn of the bilge, just a rounded, tapering hull shape with a slightly apexed/veed keel line.

    I then select the entire middle edge of the 3 edges available and crease it. I get a single-chined hull, pretty constant deadrise aft and gradually increasing toward the bow.....standard power boat, although no speed launch....lots of aft rocker.

    Anyhoo....I go to Mode : Developability Check and along the single chine there is a strip of red that goes into both sides and bottom. ...but the bottom has a blob of red at the bow, where I again assume there is a high stress. I assume that this is because FS is not really separating the plates and sees a very high stress /compound curve area? Incidentally this did not happen with my mucking about design....no credit to me for that.

    I then go to Tools/Develop Plates...and I only get the sides.
     
  5. OldNick
    Joined: Dec 2009
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    OldNick Junior Member

    OK. I tried _again_. This time I asked for 4 vertical control points. I then creased all edges to produce a double chined hull. All on a single layer. I mark that layer as developable. I ask to develop panels and still only get one panel for Port and one for Starboard.

    I also find it hard to understand the shape of the Plates that are displayed.
     
  6. OldNick
    Joined: Dec 2009
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    OldNick Junior Member

    This is what I am seeing.
     

    Attached Files:

  7. mick_allen
    Joined: Dec 2005
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    Location: vancouver, b.c.

    mick_allen -

    read the manual . . . . :

    each plate requires a separate marked layer. [also see if you can find a version closer to 3.4, I remember instabilities in the lower versions]
     
  8. OldNick
    Joined: Dec 2009
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    Location: Perth, Western Australia

    OldNick Junior Member

    I did read the manual.

    From my OP
    "The Help seems to indicate that even if I have different parts of a boat in the same layer (like, I assume topsides and bottom) , then developing them will give developments for each plate, but then it hints that placing each part of the boat in different layers will be easier to work with. Correct? Can I take the hull bottom plates/edges/chines and place them in a new layer? Should I need to? It's like the bottom plates do both exist."

    So I have read the manual and do realise that having a layer a plate may may be needed.

    I did ask how to assign different layers to each plate.

    But the manual says
    "It is best to assign each strake or part of the hull to a different layer. Then each
    layer will have its own unfolding. If a layer consists of multiple separate parts, each part again will
    have its own unfolding."


    Hence my confusion.
     

  9. OldNick
    Joined: Dec 2009
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    Location: Perth, Western Australia

    OldNick Junior Member

    OK. I hope this helps somebody else confused by this.

    The peculiar picture I posted was of _all_ the plates, still joined. I had hoped that posting that picture would trigger someone into saykng that, as I was just confused.This is because they are on one layer and are still considered joined. If they are all on one layer, they must be separate, as seen by FS. Creasing an edge does not create two separate plates.

    I also asked how to place a plate onto another Layer. This to me is a weird one.
    (1) You have to have Interior Edges set on in Visibility. By default they are not.
    (2) Once they are on, you can select Faces. Note:. You have to actually click on an Internal Edge on the face, not the spaces in between.
    (3) (And these are what I read by searching many messages). You need to: - create an empty Layer,
    - then selecte the faces that you want to assign to that new Layer.
    - Then select the new Layer in the Layer drop-down to set it as the active Layer.
    - Then _de_ select the faces you selected. This assigns them to the active layer.
     
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