I don’t know if there is an automatic tool, but I think JoinCurves will just put the curves in a sort of list. Curves that are not tangent will not be build in one single curve.
You could do that by using
Try to add always the same number of points at regular distance. If not you could then rebuild the curve with a rebuild command.
Here the blue cross represent start/end of curves. You can see that there is a point at middle positions on the curves on the left. That is not good to generate nice surfaces. On the right there is a point just at the kinks/corner.
If it is not a repetitive task I advise you to build the curve and loft with Rhinoceros. You will have a full control of the seam position and orientation. The 3dm I posted above was done in Rhinoceros.
You’re right. The method you mentioned above is really nice.
In fact, I’m processing a more complicated model than this one.
It’s so hard to deal with it manually, so grasshopper is a better choice to me, maybe.
It is hard to advise you correctly as some tools are not working well or I don’t know the trick to make them work. There are many strategies workaround to solve a problem and take into account the good and the bad of a tool. I don’t know why fit is not working.
Here a script that works with your curve.
I reuse @Erik_Beeren tool to adjust seam.
Seam is using X axis to sort seam, it will not work every time
I use my Fit component as the GH component is for some reason not useful there.
I use also an orient tool from Sasquatch.