Recently I shaped a traditional fish (my first go at Surfboard shaping). The templating and foiling went well however when it came to the rails, I wasnt sure of the rail line setup. I had boards around for reference which had excellent examples of rails to copy but I found it hard to translate a finished rail back into rail lines (how many and at what measurements). Can anyone suggest a process of working backwards from the finished rail shape to the required rail line markings ? The Rails I was after was 50/50 at the nose into a soft forgiving 60/40 into sharp edged at the fins to the tail. Board is 3 inches at max thickness. Appreciate anyones thoughts…
Anthony, This is kind of elaborate - there may be simpler ways of doing this but… You could take some numbers off the rails in a couple of spots (note distances from nose or tail). Then draw profiles from your measurements in a vector draw program, like Illustrator or Freehand. Then you get some kind of abrasive disk and attach a handle to it through the hole in the centre . Measure the distance from the handle to the edge of the disk. In your draw program offset your profile by that measurement. Print out, glue to thin mdf. cut out with a jigsaw to make a rail profile template as in pic below. Put the templates around the rails at the spots where you took your intial numbers and roll the disk along the template - it will leave a cut in the foam with exactly the profile of the original. Make a couple more and blend together with planer. 
Here is a contour jig that has been in the Archive- Tools section for quite some time. Good luck. Tom S. http://www.swaylocks.com/resources/Detailed/392.html