The Best Stained Glass Grinders: 2020 Buyer''s
· RPM (Rotations Per Minute): RPM, or Rotations Per Minute, tell you how fast the glass grinder bit is typically range from 2,850 to 3,600 rpm. The faster the rpm on your stained glass grinder, the better. Quicker rotations will help keep your glass edges smoother and will help push excess materials out of the way for a faster, more precise and efficient workflow.