a device for grinding welding electrodes comprises a driving motor , a shaft driven by said driving motor and a grinding wheel driven by said driving motor through said shaft , said grinding wheel having a first and a second grinding surface . a first guiding block is provided having at least one first opening , said first opening defining a position relative to said first grinding surface and said opening being adapted to guide a welding electrode for grinding into said defined position relative to said first grinding surface , and a second guiding block having at least one second opening , said second opening defining a position relative to said second grinding surface and said second opening being adapted to guide a welding electrode for grinding into said defined position relative to said second grinding surface .