I published an improved version which simplifies the built significantly!
Experimenting a bit more with spiral design and wood bending, this small bowl came to life. It turned out, that a little fixation using small brackets is needed.
My build was done on a desktop cnc-machine by Stepcraft from 6 mm birch plywood using a spiral-toothed 1.2 mm flute.
Visit https://www.zenziwerken.de/en/ for more interesting designs.
I used Illustrator and a script written by Sato Hiroyuki to create an approach of the Archimedes Spiral.