... .grinder 360 degree free rotating 3.cutting, grinding, milling, drilling and polishing product introduction :1 ... It can not only be used for cutting, grinding, milling, drilling and polishing stones, but also ... rotating, moving freely and automatically.5.Open the joint of the arm, the machine can do ... 5M/minhead degreeany degreehead adjust degree±10°grinding curveany in and side curvegriding head rotation ...