As I teased earlier, I started work on a second zendala with the circle string. I added basic circles in graduating sizes but tangling in just the circles seemed too easy for me - I had to complicate it somehow! So I decided to split the circle in four segments and fill in alternating sections.
I was tangling it with my friends last night and they told me it looked like an eye chart! It was fun to do this without any shading and just emphasize the graphic nature of it.