Here's another example of a puzzle using the technique illustrated at the Chicago User Group 2018.
The puzzle was created as a Christmas gift for a relative. It consists of 176 pieces and was made from a variety of cherry and maple pieces. All puzzle pieces were cut with a 1/8" 2 flute up-cut endmill. To allow proper fit of the pieces, the allowance between pieces was set to -0.005". The graphics were V-carved with a 30 deg V-bit and 0.10" max depth. Coloring was done with spray-on and hand-applied ink followed by a poly clear coat.
Next time I'll use a down cut endmill. An up-cut endmill was used to clear the flat areas during V-carving. But, it has a tendency to pull the small puzzle pieces from the table. This led to lesson 2.
Because the up-cut endmill had a tendency to pull the pieces up, I had to resort to carpet tape with aggressive adhesive. The downside was it took a very very long time to remove the adhesive from all 176 pieces.
Next time, if a do a project with this many tiny pieces, I'll fabricate a vacuum hold down.