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Redraw existing Boat Hull as exact as possible

hans_gerhardhans_gerhard Member Posts: 5
I have the following hull as obj/stl file. I would like to make changes to it, give it at thickness etc. it currently is just a surface and I am only really able to use the "use" feature to project the vertices on sketches on various planes. Is there a good way to simplify the drawing process? I want to get to a point where I have a nice solid body that dosent necessarily need to include every face/vertex from the original drawing but is as close to the shape as possible. 

My original plan was to make vertical slices through the hull and draw countours with splines that I thicken und then "loft" them together. that kinda works ok in the middle sections but on the bow that plan came to its limits. 

I feel like, with this approach Iam doing a lot of work that wont really give me a good result later on. 

The next Idea was to only project the lines of the hull where there are sharp angles, like the edge on where it goes to the deck, the keel. and this third line in between them where the general shape changes. That approach you can see in the last screenshot. I tried to use the "boundary surface" feature to create a surface between the splines but was not really happy with the results. Also this approach met its limit at the bow where it wouldnt really create the shape that i wanted.

Any help is appreciated, sadly most tutorials on that kind of stuff only help with more generic hull shapes, not when you already know what the result is supposed to look like.


  • martin_kopplowmartin_kopplow Member Posts: 261 ✭✭✭
    edited February 13
    Modeling is always much more difficult, once you know exactly what you want to get! ;0) (That's why it is always easy in demos, where you can let the tool guide you to wherever it leads ... )

    Your approach is good in principle. I'd use vertex based cross sections and guide curves for the parts of the hull, where they work, and that'll be say at least 85% of the ship. Add the foil rig details later, and try thinking like the guy who made the original model. But then, I'd switch procedures for e.g. the bow, where it might be useful to make few horizontal sections, and then use the tangency conditions available via the part already remodeled, to get a precise shape there.

    (Interessantes Boot, nebenbei.)
  • hans_gerhardhans_gerhard Member Posts: 5
    Thanks for the answer!  I made some progress using the "loft" feature with some guides where it would let me, this time lofting surfaces from edges rather than parts from surfaces.The bow remains tricky but for the time being its close enough for me. Currently having some problems getting the mirrored surfaces to create a part. I think all surfaces meet correctly at the edges but its not becoming a solid atm.  
    Ja isn tolles boot! Ob aus dem Gesamtprojekt (130cm langes RC) je was wird steht in den Sternen, aber wenn man nicht anfängt kann es auch nichts werden :).
  • GWS50GWS50 Member Posts: 374 PRO
    Try having  look at the 'Enclose' tool, it may be helpful. As Long as the surfaces are manifold it should work. You can use Planes as part of the enclose precess as well, which is most useful
  • hans_gerhardhans_gerhard Member Posts: 5
    GWS50 said:
    Try having  look at the 'Enclose' tool, it may be helpful. As Long as the surfaces are manifold it should work. You can use Planes as part of the enclose precess as well, which is most useful
    How would I use planes together with the enclose tool? it dosent give me any options. I sorta optimized my second approach and iam close enough for now I think. Now on to the next 1000 problems! 
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