A method of honing a cutting edge of a rotary cutting tool comprising inserting the cutting tool into a liquid bath having an abrasive media therein such that at least the cutting edges are immersed, and providing a relative displacement of the cutting tool and the liquid bath such that the abrasive media flows over the cutting edges. Multi-functional compounds and drug dimers, oligomers and polymers are also disclosed. The etchingcleaning liquid emitted from the edge nozzle selectively removes an unnecessary material existing in the surface peripheral area.