Y-axis parting adaptor for a cutting tool

A tool assembly comprising:

• a parting adaptor comprising:
• a cutting portion comprising:
• opposing first and second sides and a peripheral edge connecting the first and second sides, the peripheral edge comprising opposing front and rear sub-edges and an upper sub-edge connecting the front and rear sub-edges;
• wherein:
• the first and second sides define a first sideways direction directed from the first side towards the second side and a second sideways direction opposite to the first sideways direction;
• a forward direction is defined perpendicular to the first and second sideways directions and directed from the rear sub-edge towards the front sub-edge, and a rearward direction is defined opposite to the forward direction;
• an upward direction is defined perpendicular to both the first and second sideways directions and to the forward and rearward directions, and is directed from the adaptor shank portion towards the cutting portion;
• and
• a downward direction is defined opposite to the upward direction;
• and
• a single insert pocket formed at an intersection of the front and upper sub-edges, the single insert pocket comprising:
• a base jaw comprising a forwardmost base jaw surface;
• a second jaw at least partially located upward of the base seat jaw;
• and
• a slot end connecting the base jaw and the second jaw;
• and
• an adaptor shank portion connected to the cutting portion and comprising an adaptor clamping arrangement;
• a cutting insert secured to the single insert pocket and comprising:
• an insert base surface abutting the base jaw;
• an upwardly facing rake surface located above the insert base surface;
• an insert second surface abutting the second jaw;
• a forwardmost clearance surface extending downwardly from the rake surface;
• and
• a forwardmost cutting edge formed at an intersection of the rake surface and the forwardmost clearance surface;
• and
• a holder comprising:
• a holder head portion comprising an adaptor pocket to which the adaptor shank portion is secured;
• and
• a holder shank portion connected to the holder head portion, and comprising:
• a holder shank axis extending through the center of the holder shank and extending parallel with the upward and downward directions;
• a holder shank cross-sectional shape extending perpendicular to the holder shank axis;
• a forwardmost holder shank surface;
• and
• an imaginary line extending in the upward direction from the forwardmost holder shank surface;
• wherein:
• the holder shank cross-sectional shape is square or rectangular, the forwardmost cutting edge is directly above the forwardmost holder shank surface, and the forwardmost base jaw surface is within a tolerance distance DT of 2 mm from the imaginary line;
• or
• the holder shank cross-sectional shape is round, the holder shank axis extends to the forwardmost cutting edge and the forwardmost base jaw surface is within a tolerance distance DT of 2 mm from the holder shank axis.