It was Storm and Roto Grip who used rubber particles, and as far as I know they STILL do. These are the ones that you should not use sandpaper on.
Everyone else uses various "hard" particles and can be sanded with any abrasive. These harder particles made from glass, ceramic, (and who knows what else) have "edges" that smooth out over time. When you resurface them with sandpaper those "edges" become sharp again and that allows some extra friction on the lane.
For a test (to prove me right) take a Storm or Roto particle ball and polish it with any compound. Use some hand pressure, but not excessive. Your rag will turn black (due to the rubber particles).
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Lane Carter, Strike Zone Pro Shops - Salt Lake City, Utah
Brunswick Amateur Staff
www.brunswickbowling.com