Hi speedy (AL2000),

Thanks a lot for your contributions, it's very close to what i want to achieve.

I mean...very smart solution.

I'd say, based on all the interesting suggestions that all of you gave me, i think that now i've got a sufficient set of tools in my Moi's toolbox,
in order to get better results in modeling this sort of things.

Above all, i learned these three things :

1) Using more relaxed and less stretched source curves leads to smoother surfaces,
2) Not always, having curves with few control points turns out to be a good idea,
3) It's not so simple build joined surfaces with a decent G2 (at least) continuity :)

I understood that my modeling approach has a recurring defect in itself :
take for granted that building things with less control points as possible, leads to get smoother objects with the best surface continuity.

The problem is that i'm not still able to understand where to puts additional control points in order to get better results.

Anyway....thanks to all for your suggestions and have a nice day!

P.S. Ti ringrazio "speedy (AL2000)" per avermi scritto in italiano!
(Thanks a lot "speedy (AL2000)" for your reply written in italian!)

Marco.