Hi Pilou,

> And make rotate 60 then 15 of a cutting plane is not sufficient without move the cylinder?

I don't think it is - the second rotation changes the "as viewed" (projected) angle of the plane's surface normal direction.

Basically the Top and Front views are both connected to one another because they share the same right-left x-axis direction. So if you do any transformation in the top view that changes position in the x axis (including rotation), it will disturb the angle as viewed in the other view.

When you want things to adhere to a particular 2D silhouette it's usually better to work more with the silhouettes and have those extruded...

- Michael