Welcome, Guest
Username: Password: Remember me
  • Page:
  • 1
  • 2

TOPIC: Hull Modelling with stations only

Hull Modelling with stations only 1 month 1 hour ago #5713

  • Axel_H
  • Axel_H's Avatar
  • OFFLINE
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Hi,
is it possible to model a hull without buttocks and waterlines just with transversal sections in Delftship? For example there is only a bodyplan that contains no lines, just the front and aft view. Would that be possible? I am used to NURBS software but this tool is hard :dry:


Thanks,
Axel
The administrator has disabled public write access.

Hull Modelling with stations only 4 weeks 1 day ago #5715

  • iosif
  • iosif's Avatar
  • OFFLINE
  • Expert Boarder
  • Romanian citizen, designs & builds small boats
  • Posts: 116
  • Thank you received: 7
  • Karma: 1
If you open DelftShip you have "Load", "Import", you will see the options you have.
See if one of them is what you need

Best wishes
Iosif
The administrator has disabled public write access.

Hull Modelling with stations only 4 weeks 1 day ago #5716

  • Axel_H
  • Axel_H's Avatar
  • OFFLINE
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Thanks! What I mean is, I use a bodyplan with transversals only as a background image. Would that be possible to build a hull from that only? I saw tutorials which all have full linesplan with buttocks and waterlines as well as the transversal bodylines.
The administrator has disabled public write access.

Hull Modelling with stations only 4 weeks 1 day ago #5717

  • Maryak
  • Maryak's Avatar
  • OFFLINE
  • Gold Boarder
  • I was tired, today I am retired
  • Posts: 178
  • Thank you received: 25
  • Karma: 4
Yes provided you know the stations, (transversals), locations along the keel line and vertically up from the baseline.

HTH
Regards Maryak
The administrator has disabled public write access.

Hull Modelling with stations only 4 weeks 6 hours ago #5718

  • Icare
  • Icare's Avatar
  • OFFLINE
  • Gold Boarder
  • Posts: 183
  • Thank you received: 31
  • Karma: 5
Hi, Axel!

Drawing a ship just using the stations and knowing the total length is just what I did yesterday. :woohoo:

First I started a project for the first sketch, asking Delftship to draw just a rectangle (same length than the ship), I changed its angles' coordinates to superimose it on the vertical plane of symmetry.
Then I imported the picture as a background image and centered it according to the plane if symmetry (shown by my rectangle).
I positioned the top of the rectangle at the ship's half beam distance.
I determined the stations intervals (comparing their number and the total length), then I divided the rectangle in as many parts as there are stations.
I moved the superior angles back to the symmetry plane.
I moved the mesh angles to their position to determine the edges final position.
The draft was done. Top view and side view were loooking well.

Then I divided horizontaly into four the rectangles, which followed more or less the diagonal slicing.

And now, the most boring: I moved each point, one after other, until I got the model's stations superimposed to the background image. The problem was that when moving a point you don't change only the corresponding station profile but the surrounding stations' profiles too.

Neither the keel or the rudder were shown on the background image, so I had to guess. :whistle:

Does it sound clear? :unsure:
The administrator has disabled public write access.

Hull Modelling with stations only 4 weeks 1 hour ago #5719

  • Maryak
  • Maryak's Avatar
  • OFFLINE
  • Gold Boarder
  • I was tired, today I am retired
  • Posts: 178
  • Thank you received: 25
  • Karma: 4
Sounds good to me with one proviso.......................Stations are not always evenly spaced longtitudinally, i.e. the number of frames between station x and station y may not be the same as the number of frames between station a and station b.

It is usual to have more stations at the extremities, (bow and stern), where hull shape changes are more pronounced than midships where hull shape between frames is very similar, if not the same with high block coefficients.

HTH Maryak
The administrator has disabled public write access.

Hull Modelling with stations only 3 weeks 6 days ago #5720

  • Axel_H
  • Axel_H's Avatar
  • OFFLINE
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Hi Icare,

thanks for your explanation or brief tutorial how you did. It does not sound completely clear, but not weird at all :lol:
So I will try to get it same way..

Cheers,

Axel
The administrator has disabled public write access.

Hull Modelling with stations only 3 weeks 6 days ago #5721

  • Axel_H
  • Axel_H's Avatar
  • OFFLINE
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Commonly, if you have a bodyplan with the transversal section from a shipyard, it is divided always in the same distance based on the LPP. As you said, fore and aft part is rather complicated designed hence they sub-divide the stations by half, but always the exact distance.
If you have a final framing plan where all frames are shown (can be 200 or more depending on the vessel's length) then you have to stick with the frame distances shown on each general arrangement plan.

But as above mentioned, the bodyplan for initial construction of a hull, they have either 10 or 20 stations with same distance (and fore / aft half stations or even quartered) I guess this is why they call it stations and not frames, because frames are rather on the final framing plan which indeed show each single frame in shape.

Cheers,

Axel
The administrator has disabled public write access.

Hull Modelling with stations only 3 weeks 6 days ago #5722

  • Icare
  • Icare's Avatar
  • OFFLINE
  • Gold Boarder
  • Posts: 183
  • Thank you received: 31
  • Karma: 5
Maryak:
You're right, distance between station can change at the very ends of the hull, but when it happens, you can see there's something odd on the top view (the bow or stern will be pointing out in a aesthetic-displeasing way), then try to divide this station's interval by two, and if it still doesn't work well, you'll have to guess the right distance by trial and error.

Axel:
When there are too many stations (I forgot to mention this eventuality), you can simplify the net (use less polygons) and let the software draw more than one station per mesh. I'm used to say about the meshed net "the simpler is the better", because is easier to draw it and to modify it, too. ;)
If you really can't get the model's stations profile fit the background image, you'll have to add a row of meshes (depends on the curve's complexity).
I'll try to post scrennshots on the next week.
The administrator has disabled public write access.

Hull Modelling with stations only 3 weeks 6 days ago #5723

  • Axel_H
  • Axel_H's Avatar
  • OFFLINE
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Hi Icare,

thanks for the input again and well what you mentioned to Maryak, correct, an odd distance is not common and if it happened you can adjust it on the forcastle outline.
Looking forward seeing your screenshots :)

Cheers,
Axel
The administrator has disabled public write access.
  • Page:
  • 1
  • 2
Time to create page: 0.114 seconds
Powered by Kunena Forum