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The paper presents the distribution of contact stresses on the flank land of a cutter during steel turning (Fe-0.4C-1Cr) at the initial time of cutting. Plunge-cutting into a steel workpiece by the whole length of the cutting tool edge features almost twofold short-term increase of in cutting force components in comparison with stable cutting. Such increase is absent, if the feed rate exceeds 0.34 mm/rev and the cut depth exceeds 2 mm. This is explained by sagging of the cutting surface under the influence of the dead zone in the area of the cutting edge, which moves before the cutting tool and reduces the contact interaction of the flank surface chamfer with the workpiece. The contact stresses on the flank surface chamfer increase with the distance from the cutting edge, which is explained by recovered cutting surface sag, conditioned by the action of the dead zone in the cutting edge area. This increase accelerates with the reduction in the feed rate. Normal contact stresses increase more quickly on a flank-land at a distance from the cutting edge of more than 0.8 mm, which is explained by recovering of a transient surface sag, and explains the increase in the probability of cutting wedge destruction when the length of flank-land wear exceeds 1.2 mm.