Reply To: Curve cut in Sphere shape

HI Dieter,

Modeling this would be really hard (but possible).

What you could try, as this is for printing, is to use Sculpting, with the Stroke set to Curve:

Kent demonstrates this method in the Core Fundamentals of Sculpting in Chapter 1 Lesson: Stroke Methods from ~3:38.

Of course, the Boolean workflow that Steven suggests is also an option.