Sphere off a cilinder

[joaonc]

How do I take out a sphere from a surface? See the images attached for what I'm referring to.
The way I did those was by specifying the Mill edge to be round with a radius of 8mm, which is the maximum. However this only allows for a maximum of a 16mm diameter sphere and I need something bigger (40mm).

Thanks in advance,
- Joao

[joaonc]

By the way, the material is aluminum.

[Tech2]

Please see Revolve.

[joaonc]

Thank you for the quick reply, but I don't see how the lathe machine will work. The sphere is to be taken out from the middle (Z axis), whcih is where the piece is revolving.. am I missing something?

[Tech2]

The software will usually warn you if something is not machinable. You need to create the 90 deg arc in the side view where the Revolve line is.