Mechanical residual stress in a machined surface was studied experimentally. Structural change was eliminated by machining low-carbon steel under selected conditions. The shape of the cutting edge was found to govern the residual stress near the machined surface while the length of the shear plane was found to govern the bulk distribution of the stress. It was also found that smaller depth of cut did not always produce lower stresses. The effect of the degree of constraint in the deformation process on residual stress formation was demonstrated by using orthogonal, oblique, and conventional cutting processes. It was observed that a lower degree of constraint in the deformation process produced a lower level of residual stress.