Was this supposed to be journalism?

So it will ultimately come down to what file format you need for the 3D printer and if Blender can support that. Otherwise, you may need to generate your geometry using a CAD program.

Regardless, you will need to generate the solid model of your cylinder. In this case you’d extrude your cylinder surface to create a volume body and not a sheet or surface.

On Firefox, you can click reader mode and that often bypasses the walls.

“The Man Inside Me” by Tobias Fuenke