How To Make It Using the circular object for a pattern, trace a circle on the navy blue corrugated plastic. Cut out the navy blue circle with the extremely sharp scissors. Add tacky glue to the end of the stick and push up inside the baseball. If using tacky glue, allow to dry overnight. Tips You can also use regular cardboard and paint it if you can't get corrugated plastic, but it won't be as durable.
Corrugated plastic is made by several manufacturers.
It is known as Stratocore or Coreplast, along with other names. I found that if I purchased it from a signage store it was cheaper as long as I was going to make several projects out of it. Otherwise, open it.