I originally posted this message to the Yahoo Deckplans Group last year, but did not get much feedback. 
Re-posting it here for anyone that is interested.
Here's what I have done to try and fit a regular deckplan into an external view. First I load a desckplan into a 3D program by mapping it onto a flat plane. I then add a series of boxes, 2 units high on all of the staterooms and other internal spaces. These I group together to stop them getting accidentally moved. Next I delete the
plane with the deckplan on it and then repeat the procedure for each additional deck. Once each 'deck' is constucted you can line them up vertically and join them together. Now you have a solid box structure representing the interior of the ship.
Now for the 'fun' part. If this is a standard ship, compare what you have with the published external view. Guess what, in most cases there is no way it will fit and keep anything like the streamlined shape shown in the external views.
Here's the deckplan/gearhead part. In most cases it will be necessary to slope or curve some external walls to make them fit within the ships outer hull. On most wedge or cylindrical hulls I have found that, on average, you usually end up sloping the top or bottom cube of each square by about 45 degrees.
As a general rule then: each dton that is adjacent to a streamlined hull will loose about 1/4 of it's volume due to the slope or curvature of the outer hull. Of course, this also depends on the actual shape of the hull. For example I would assume that on a 3 deck wedge the middle deck has normal vertical walls. The savings of .25 dtons is not much, but on most ships this will give you a couple of tons at least. It's also more realistic than assuming that all staterooms etc. are all just boxes.
Re-posting it here for anyone that is interested.Here's what I have done to try and fit a regular deckplan into an external view. First I load a desckplan into a 3D program by mapping it onto a flat plane. I then add a series of boxes, 2 units high on all of the staterooms and other internal spaces. These I group together to stop them getting accidentally moved. Next I delete the
plane with the deckplan on it and then repeat the procedure for each additional deck. Once each 'deck' is constucted you can line them up vertically and join them together. Now you have a solid box structure representing the interior of the ship.
Now for the 'fun' part. If this is a standard ship, compare what you have with the published external view. Guess what, in most cases there is no way it will fit and keep anything like the streamlined shape shown in the external views.
Here's the deckplan/gearhead part. In most cases it will be necessary to slope or curve some external walls to make them fit within the ships outer hull. On most wedge or cylindrical hulls I have found that, on average, you usually end up sloping the top or bottom cube of each square by about 45 degrees.
As a general rule then: each dton that is adjacent to a streamlined hull will loose about 1/4 of it's volume due to the slope or curvature of the outer hull. Of course, this also depends on the actual shape of the hull. For example I would assume that on a 3 deck wedge the middle deck has normal vertical walls. The savings of .25 dtons is not much, but on most ships this will give you a couple of tons at least. It's also more realistic than assuming that all staterooms etc. are all just boxes.
