I never thought about it being a "zen" thing but I've done this sort of doodling since I was in middle school and come to think of it, I'd do it when I was nervous, upset, or overwhelmed. ( I usually 'doodle' when I'm bored)
recently i have upload picturs of japanese rocking chair i build 10 years ago and how it looks today . i have found the pictur of this chair when it was new . it has no glue and can be Detachable to its components .