How to organize tracings from ship's lines?

[mcg]

Recently I located a set of ship's lines for the SMS Emden I. I thought I would try to recreate the hull in Rhino 4.0 as a learning exercise.

As you know, the section lines are, on paper, stacked on top of one another. My intuition is that each section line needs to be traced -- and then pulled off to one side or filed in a numbered parts bin.

The next step would be to space them out and assemble them, one by one, to the keel line.

I was wondering how best to keep all these section lines sorted out in Rhino?

I suppose I could assign each line to a layer, and then hide the finished layers as I trace each new line. Another way might be to use numbered files or Blocks for each line?

In any event it is a problem that begs for some sort of logical system -- just wondering how you all tackle it. It is not unique to Rhino, probably a system of some sort would find application in ACAD and other programs as well.

In model airplanes, the organization and numbering problem solves itself, because the input is usually a scan from printwood. The formers are already spread out on a plank, an none of them are superimposed.

Thank you for your insights, Michael

[Cadman]

In AutoCAD it's best to create layers for them and as you say assemble them along the keel at the various matching frame numbers. I can't speak for Rhino and other programs, but I have found it best to plan how the lines are drawn. When you get to the lofting stage, it helps to have equal points to loft to and from.

If you are able to find real plans you will find that most ship yards have detailed drawings of each line along with the interior details of the ship drawn at each and every station. Those are much better to work from than the typical overlapping hull lines. I draw a complete outline of one half of the hull section at every frame. Much like the scratchbuilders do their large scale ships. I then use the lofting tools to extrude a closed surface from frame to frame. It can be a trial and error process sometimes as the curves don't always flow like they should.

[mcg]

Thank you. I have some of the cross sectional drawings, although there are fewer of these than the ship's lines. In other words, I don't have a detailed cross sectional drawing corresponding to each section, only a few. However, with Rhino, it often seems that the fewer the frames, the fairer the curve.

I can see why the cross sectional drawings would be better -- because they are not overlaid. There is no confusion about where a line starts and stops.

[Cadman]

It is best to work with the largest scale drawings you can find. Then as I mentioned plan your curves carefully. I go so far as to try to make my sections equal to a typical plate height. In AutoCAD sometimes when you are lofting from say 15 points down to say 11, the loft will flip, or just get confused about the direction it needs to go.

[mcg]

What I have here is an assortment of plans and drawings scaled variously at 1:200, 1:100, and 1:50. They are well drawn. I will take the collection over to Kinko's and get the sections and lines scanned. As I get into it, and more questions come up, I will post some Rhino screenshots. Thank you again for your help. Regards, Michael