String Art for Boys Room

We are not a sports family. We haven't ever watched a game of anything on TV. I grew up playing soccer, dancing, and for a while I was in gymnastics, but my husband didn't play anything. He had a four wheeler, the hills behind his home, and he lived in the desert. My oldest son doesn't play sports either and is just like his dad. He loves to be outside hiking, camping, four wheeling, exploring, and playing the guitar.
I had to get a bit creative when decorating his room. One of the things he loves is trucks. He can't wait until he can drive and he asks questions constantly about traffic laws, driving heavy equipment, and anything related.
String art has been popular and I decided to make him a string art stop sign. I had my husband cut out the octagon in a piece of plywood we already had. Then we nailed the border in roughly an inch apart (no measuring, we guessed). I printed off STOP and cut it out to trace onto my sign. Then I popped in a movie and began stringing. It's not nearly as bad as it looks. Take not that after ten minutes or so of stringing, I tied a knot and began another string. This is only because I was terrified that if it popped off an began to unravel that it'd be a huge mess. I was taking extra precaution.
This thing is big, about two feet in diameter.