Modular rotary cutting tools

A modular rotary cutting tool comprising:

• a shank having a central longitudinal axis and comprising a central pin-receiving hole and a front pocket, the front pocket comprising:
• first and second opposing pocket centering walls wherein each of the first and second opposing pocket centering walls are disposed at a seating angle S of greater than 0.5° measured from the longitudinal axis of the shank;
• first and second torque transmission pocket drive walls;
• and
• a pocket floor;
• and
• a cutting insert removably installable in the front pocket of the shank comprising a pin receivable in the pin-receiving hole of the shank,
• wherein the first pocket centering wall defines a plane, the first pocket drive wall defines another plane, the first pocket centering wall plane and the first pocket drive wall plane intersect at a pocket intersection point P located at the pocket floor at a pocket wall angle A measured at the intersection point P, and the pocket wall angle A is from greater than 90° to less than 155°, wherein each of the first and second pocket drive walls are spaced apart from each other in planes parallel with the longitudinal axis of the shank such that a virtual extension of each of the first and second drive walls project unobstructed across a diameter of the front pocket.