Naval Architecture question

Is there a method in rhino to draw the battens on a hull so they will lay fair? I have tried pulling the centerlines of the battens to the surface, not the best results. looking to achieve the natural lay of a batten on the bottom frames as they take a twist from horizontal at the transom to vertical at the stem…

Different ways of achieving what you ask. I am not sure about what your are calling the battens but I often have to run stringers or bulb-t’s in aluminum boats and probably the best I have found is to create a curve on my hull surface running from where it is at the transom to where I want if on the stem. Then adjust where you want the midpoint of that stringer or batten sweep to where you want it at midships. Check for the fairness to your eye or the analysis tools. Then use that line on the surface to create a ‘ray’ which will be follow the normal of the hull surface. That will account for the twist you mention. Then you can offset that ray on both sides to create the width of the batten and its edges. Then you can create the inner and outer surfaces of the batten using ‘edge surf’ from two edges and close in the batten.

Another way is to use the curve on the hull surface and pipe it and intersect with the hull surf to create two curves on the surface which can be used as a Sweep 2 Rails and a profile of an aluminum extrusion such as a Bulb-T.

Thanks for your reply, The battens are the wooden members that lay on the frames fore and aft that provide support for the hull surface and provide a structural member for fasteners. Bottom battens in traditional built wooden boats are typically 1/2" x 1 1/2" . I dont have an issue with creating the lines used to create the surface. How do I get the batten to lay fair on the frames in the real world? For example, Its like wrapping a yard stick around a cone… A square stick of wood will bend relatively fair, as will a round one, a rectangular one has to lay fair to the frame or it will buckle between the frames.

You could ask on the WoodenBoat forum. forum.woodenboat.com