Removing a core from a model

[Box]

Here’s an animated version of what @DaveR mentioned above with a different pattern.
You can make the pen blanks and then use Intersect Faces with Model to get the edges that would form if it was made of sections.
This is an example that uses a single ‘Plank’ component to cut a design into a turned shape.

Out of the Box

Just to explain the above ‘curling stone’. It was the wood turning gif that made me construct this. [Laminate] I used the component block to create the pattern on the surface of a sort of torus. Then I painted the pattern black where I wanted. This allowed me to ‘select all with the same material’ and JPP it to get the depth.