Yes Pilou, you are right.

In Help file, it's written about network : "It is not necessary for the curves to exactly intersect,"
But, if the Network tool works fine in the 3dm scene I first posted, it doesn't work anymore on my new scene....maybe too much attempts, and other tools used...so I start over a new one.

Question : is it a problem to make a network with different kind of curves (point surves and control points curves...) ?? ?

Note : the problem with the Network/gordon + Mirror method is the tangents...symetry is not perfect and it's a bit tricky to adjust points to achieve a perfect mirrored object... ....
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