Computer hydrostatics reliable? carene / delftship

Discussion in 'Software' started by stonedpirate, Apr 10, 2010.

  1. stonedpirate
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    stonedpirate Senior Member

    Hello,

    I created a hull in carene at it said my displacement at waterline was 1 tonne. Delftship said it was 2 tonnes.

    Does carene only work on half a hull?

    Not sure what to trust :)
     
  2. stonedpirate
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    stonedpirate Senior Member

    hmmm

    It doubles in delftship if i apply a mirror.

    Without a mirror i get the same volume as carene.

    Must be a bug in delfship.
     
  3. stonedpirate
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    stonedpirate Senior Member

    here is the delftship file

    Are the hydrostats for half the hull or both and the mirror is a bug?

    Or does mirroring it create the full hull and the stats are right?
     

    Attached Files:

  4. stonedpirate
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    stonedpirate Senior Member

    This is killing me.

    Even freeship doubles everything to a mirrored hull.

    Quite a crucial bug.

    Should i use the half hull or mirrored hull displacement?
     
  5. masalai
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    masalai masalai

    If the drawing is done well then Delft/Freeship come from the same family... Test it out by making a rectangular box draw a half say 10m x 10m x 40m so when mirrored it should show 20m x 10m x 40m and draw the waterline then you can easily verify what is what...

    Preset the waterline to 1m or 0.5m whatever takes your fancy... USE metric then the answer is in fresh water and 1kg = 1litre = 1000 cubic-centimetres
     
  6. stonedpirate
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    stonedpirate Senior Member

    Good idea.

    I'll test it
     
  7. stonedpirate
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    stonedpirate Senior Member

    Man i suck at splines

    I'm a poly modeler with a max background.

    Cant even draw a box with splines :p

    Do people here use mirrored displacement or not?
     
  8. masalai
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    masalai masalai

    gets both sides the same... Works for me...
     
  9. stonedpirate
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    stonedpirate Senior Member

  10. lewisboats
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    lewisboats Obsessed Member

    Delftship and Freeship work with only one side of the hull...as generally hulls are symmetrical side to side. The displacement figures are correct for the whole hull. If you mirror you essentially double all the hydrostatics. If you wish to see the half hull as whole there is a button for it. It looks like a half red half green hull coming at you. Whatever you effect on the one side will be the same on the other. Remember...both freeship and delftship were originally designed to build SHIPS... of which 99.99999999 percent are Monohull so Cats are a whole 'nother problem...and that is where the mirror command comes into play...also if you create .parts then mirroring is useful also. Time to break out the manual and thoroughly read or re-read it...
     
  11. stonedpirate
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    stonedpirate Senior Member

    cool

    thanks a lot Lewis :)
     
  12. masalai
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    masalai masalai

    I think SP is still too stoned to think or read... ???
     

  13. stonedpirate
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    stonedpirate Senior Member

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