Quote - I'm not sure I understand why you think it's the math of the surface that makes the problem.  As far as I can tell, it's a pretty basic issue that you'd see in any shape with a non-uniform width or height, even a planar triangle. 

It looks like your problem is very simple: you're changing your density with your width.  In real life, the density of the weave would never change, but the amount of it would.  The ribs would lead down and stop when they hit the edge.  So the middle might be as you'd have it now, but the the top and bottom would  have at least one more rib on either side.  Given the current spacing of ribs, of course.  Or, in the first design, the woven parts would stop when they hit the edge.  Just like you've got them doing horizontally in the second design.  As they followed a path in the z and y planes, they shouldn't have shifted in the x direction.

But maybe I'm missing something.

If you look at the final design, I've got weaving technique figured out, and corrected that shifting problem.  I could add one more on either side in the wider areas, and just cut them off at the border, as that would be more correct.

The issue initially was in the technique I chose to use, which wasn't working out for this kind of shape.  The technique of extracting splines from the original mesh edges was getting screwed up because of the variable density required for this kind of curvature.  I needed to find a different solution, as I wasn't about to manually place each and every weave along the surface area, even though that would be the most accurate way.

Thanks.

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