I have two Bézier curves parallel to each other ( for example see first picture), I created guide curves joining the control points of these splines (first picture also).

My objective is to loft a solid using the style splines as profiles such that the parallel sections of the resulting body are also Bézier curves with control points defined by the intersection of a parallel plan and the guide curves ( see picture bellow).

I tried to loft a solid using the two splines and the guide curves (all the guide curves are defined in a single 3D sketch). The difference between a section of the obtained loft and the desired one (highlighted in blue) is shown in the picture bellow.

Any suggestions ?Thanks for your answers.