Laser etching seems to be the way to go. There are rotary attachments for laser cutters as well so you can engrave cylindrical objects.
Alternatively, consider hydrographic printing/dipping which can be used on any 3d geometry
Laser etching seems to be the way to go. There are rotary attachments for laser cutters as well so you can engrave cylindrical objects.
Alternatively, consider hydrographic printing/dipping which can be used on any 3d geometry