: turn the control net off and on to get an idea where the yak really is. and
: then turn the surface edges (the surface network) on and off at high to
: see how flat(or whatever you are going for) the surface is.

Actually when importing chines, the FreeShip generated curves that approximate them are actually chines (crease edges, I mean). So the S&G nature is preserved that way, however there are some curves that are fitted poorly especially near the razor sharp chine and stern. The model check tells me I have leak points. When importing chines the docmentation does not explain if the chines have to go all the way from aft to front or over smaller sections. For modeling the cockpit for instance, importing lines that follow the chines all the way from aft to front around the cockpit inevitably leads to unwanted interpolations.

So it is not really all that bad but I still end up spending lots of time guessing about the smarts of FreeShip and still ending up with poor interpolations and model errors.

The original model really does not have that much data: here it is, all coordinates in mm starting with a 15' x 28.75" basic model, interpolated, stretched and rockered with a few simple commands to the final model (http://members.cox.net/aling13/kayak/build/fall_2007/combinedView.JPG):

data = [
// y, x1, z1, x2, z2, x3, z3, x4, z4, x5, z5;

0, -100, 310, -101, 0, -101, 0, -105, 0, -100, 310;

250, 0, 155, -1, 0, 48, 280, -5, 0, 0, 300;

500, -100, 0, -101, 45, 95, 250, -5, 0, 0, 290;

750, 0, 0, 70, 80, 145, 215, -5, 0, 0, 280;
1000, 0, 0, 120, 90, 195, 190, -105, 0, 0, 270;
1250, 0, 0, 180, 80, 250, 165, 100, 250, 0, 270;
1500, 0, 0, 220, 70, 295, 155, 190, 240, 0, 270;
1750, 0, 0, 255, 60, 325, 150, 250, 230, 0, 260;
1875, 0, 0, 270, 50, 340, 145, 270, 230, -100, 250;
2000, 0, 0, 280, 50, 350, 145, 280, 230, -4, 0;
2250, 0, 0, 290, 50, 360, 145, 300, 230, -4, 0;
2500, 0, 0, 270, 50, 350, 150, 280, 240, -100, 330;
2750, 0, 0, 245, 70, 330, 155, 260, 250, 0, 330;
3000, 0, 0, 210, 90, 295, 165, 230, 260, 0, 330;
3250, 0, 0, 160, 90, 235, 185, 150, 270, 0, 320;
3500, 0, 0, 115, 80, 185, 210, 80, 290, 0, 310;
3750, 0, 0, 65, 60, 140, 240, -105, 0, 0, 310;
4000, -100, 5, -101, 40, 90, 280, -5, 0, 0, 320;
4595, -100, 370, -101, 0, -101, 0, -105, 0, -100, 370
];

The negative X coordinates indicate references to other lines (duplicates where lines join, another added -100 indicates a line dertivative discontinuity. Only 155 data points and some negative numbers that define the topology.

The problems with importing chines in FreeShip are with the topology (the negative X numbers in the above matrix). How do I tell FreeShip to interpolate exactly from here to there.

Well I could go with the FreeShip approximation that I have since I don't expect exact answers from the hydrodynamics anyway, I just don't know how bad the model errors (leaks) are for the results. Could the model sink with too many leaks ;-) ? I went overboard already, I think.

Henk