Milling tool with helix angle transition

A method for designing a milling tool having a front end, a rear end, and a longitudinal axis extending therebetween, wherein the milling tool comprises a shank portion and a cutting portion, which extends along the longitudinal axis from the front end towards the shank portion, and a plurality of teeth separated from each other by a corresponding number of flutes, wherein the teeth extend axially along the cutting portion following a curved helical path around the longitudinal axis, wherein each tooth extends at a first helix angle from the front end to a helix transition, and at a second helix angle from the helix transition towards the shank portion, wherein the method comprises the steps of:

• subjecting a force algorithm, designed for calculation of simulated cutting force during simulated machining of a surface of a workpiece with a milling tool, to an optimization routine in which the objective is to minimize the difference between the maximum force and the minimum force in a direction normal to the surface of the workpiece, and in which the variables are at least two of:
• the first helix angle (α),
• the second helix angle (β), and
• an axial location of the helix transition along the cutting portion;
• and, designing the milling tool on basis of the combinations of the first helix angle, the second helix angle, and the axial location of the helix transition, found to be optimal.