Mr. Vadim, please, can you explain why you use the term torque to characterize the cutting action of a knife? (Generally it is used to describe rotation effect of force. In US physics the word torque is used, while in UK and the EU torque is referred as moment of force abbreviated as moment.)
In my understanding the torque it is fully adequate to describe a cutting action when the knife tip rests on the board and serves as a lever fulcrum.
My understanding of the mysterial increase of edge sharpness observed in your experiment is following: deburring the knife edge using low speed hard felt wheel impregnated with 1 micron diamond abrasive results in edge surface with roughness cca 0.1 micron. That can be considered a nice, clean smooth surface, until we realize, that the apex diameter is only some 0.2 or 0.3 micron (for edge with BESS score 100 or 150). Some of the edge surface irregularities may be caused by burr residua which were more firmly attached to the edge and survived the deburring. The experiment shows that repeated movement of the edge in a 32⁰ V groove can remove/smooth some residual edge surface irregularities and lower the BESS score.
As mentioned by Mr. Vadim on another occasion, edge burnishing may also play some role in the explanation of this experiment.
Jan
In my understanding the torque it is fully adequate to describe a cutting action when the knife tip rests on the board and serves as a lever fulcrum.
My understanding of the mysterial increase of edge sharpness observed in your experiment is following: deburring the knife edge using low speed hard felt wheel impregnated with 1 micron diamond abrasive results in edge surface with roughness cca 0.1 micron. That can be considered a nice, clean smooth surface, until we realize, that the apex diameter is only some 0.2 or 0.3 micron (for edge with BESS score 100 or 150). Some of the edge surface irregularities may be caused by burr residua which were more firmly attached to the edge and survived the deburring. The experiment shows that repeated movement of the edge in a 32⁰ V groove can remove/smooth some residual edge surface irregularities and lower the BESS score.
As mentioned by Mr. Vadim on another occasion, edge burnishing may also play some role in the explanation of this experiment.
Jan