7 Angle Grinder Uses. How to Use this Versatile Power Tool
Grinding time and pressure of the mortar can be adjusted and fixed, saving time and labor. The first automatic Mortar Grinder was invented by F. Kurt Retsch in 1923: the "Retschmill". Advantages. The use of mortar and pestle, pestling, offers the advantage that the substance is crushed with low energy so that the substance will not warm up.