fix down extract static from a part into materials
static_friction is not surface_force_vector. grinding is material_handling. statics is mechanics. digging_up_root is removal_by_moving. static_friction is surface_force_vector. spreading_stuff_onto_surface is applying_stuff_to_surface. statics is not mechanics. static_friction is not friction_vector. static_friction is friction_vector. drill_bit is cutting_implement.