Thanks everyone!
The pyro is essentially freehand, the basic layout used the indexing feature of the lathe to ensure symmetry of the patterns. Once those pencil layout lines were in place, all the burn lines were freehand. The pyro was done over the course of a few days between getting home from work, and dinner. Not really sure how much time involved, there are around 850 burn lines.
I practiced this and other patterns with paper and ink until they began to become second nature, then tried it on scrap wood with woodburner to make sure there would be no major surprises.